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AEM Glossary




This standard defines the format and content of an electronic fileset that comprises a digital talking book (DTB) and establishes a limited set of requirements for DTB playback devices. It uses established and new specifications to delineate the structure of DTBs whose content can range from XML text only, to text with corresponding spoken audio, to audio with little or no text. DTBs are designed to make print material accessible and navigable for blind or otherwise print-disabled persons. The ANSI/NISO Z39.86 standard is also known as "DAISY 3."
ANSI/NISO Z39.86 information

APIP (Accessible Portable Item Protocol)

APIP is an XML-based standard for computer-based testing and assessment. It allows content to be transferred and to be made accessible. Transferable content can be used and/or moved between systems and databases. Accessible content, in this context, consists of specifying student needs prior to assessment using an individual profile that works in conjunction with test content and the testing interface and environment.


Unformatted text with each letter represented by a number conforming to a standard developed by the American National Standards Institute (ANSI) to define how computers write and read characters.
ASCII Codes Table


In the context of technology, accessibility most commonly refers to providing access for all people to web environments, including people with disabilities. Designing sites for the way that screen readers, text browsers, and other adaptive technologies interact with the web; choosing contrasting colors for readability; and providing alternative text tags for graphics are examples of making websites more accessible.

Accessibility Standards

Footnote 9 of the RFP that established the National Center for Accessible Education Materials for Learning states:  As used in this priority, ''accessibility standards'' means current or revised electronic and information technology accessibility standards (EITAS) developed and implemented under the authority of Section 508 of the Rehabilitation Act (29 U.S.C. 794d(2)(A)) as well as interstate and international communication access guidelines authorized under the Telecommunication Act Accessibility Guidelines (47 U.S.C. 255). The use of designs or technologies as alternatives to the EITAS is permitted provided they result in substantially equivalent or greater access to and use of a product for individuals with disabilities (36 CFR part 1194.5). The annual Section 508 Report to the President and Congress indicated the most common accessibility standards used by recipients of Federal financial assistance are Section 508 EITAS and the Web Content Accessibility Guidelines.

Accessible Educational Materials (AEM)

Accessible educational materials, or AEM, are print- and technology-based educational materials, including printed and electronic textbooks and related core materials that are designed or converted in a way that makes them usable across the widest range of individual variability regardless of format (print, digital, graphic, audio, video).

Accessible Instructional Materials (AIM)

Accessible instructional materials, or AIM, refers to print-based educational materials that are converted into specialized formats (e.g., braille, large print, audio and digital text).  As IDEA (the Individuals with Disabilities Education Act) specifically focuses on the provision of accessible formats of print instructional materials, the term AIM is used when referring to accessible materials related to the requirements of the IDEA statute and regulations.

Accessible Media Producers (AMPs)

Accessible media producers (AMPs) produce specialized formats of instructional materials such as braille, audio, digital text, or large print for use by blind or other persons with print disabilities. Accessible media producers are eligible to download files directly from the NIMAC as agents of authorized users. Major AMPs supported by the U.S. Department of Education and involved in NIMAS work include the American Printing House for the Blind (APH), Bookshare, and Learning Ally (formerly RFB&D).

Accessible Technology

Accessible technology is technology that can be used by people with a wide range of abilities and disabilities. It incorporates the principles of universal design. Each user is able to interact with the technology in ways that work best for him or her. Accessible technology is either directly accessible (usable without assistive technology) or it is compatible with standard assistive technology. In the same way buildings with ramps and elevators are accessible, products that adhere to accessible design principles are usable by individuals with diverse abilities, needs and preferences. Definition adapted from one originally shared on 

Alt Tag (alternative text)

An alt tag is a brief description of a single image designed to be read by a screenreader as an alternative to that image. Alt tags are approximately 4–10 words long and state the type of image and a brief summary of it; when possible the alt tag expresses the purpose of the image as well. Alt tag text does not interpret an image (i.e., smiling, not happy). A producer's note (prodnote) or long description (LD) is used to provide a full or comprehensive description of an image, chart, or graph.

American Foundation for the Blind (AFB)

The American Foundation for the Blind is a non-profit organization that expands possibilities for people with visual impairments. AFB has been advocating for the rights of people who are blind or visually impaired for more than 80 years.
AFB website

American National Standards (ANSI)

The American National Standards Institute (ANSI) is a private, non-profit organization (501(c)3) that administers and coordinates the U.S. voluntary standardization and conformity assessment system. The Institute's mission is to enhance both the global competitiveness of U.S. business and the U.S. quality of life by promoting and facilitating voluntary consensus standards and conformity assessment systems and safeguarding their integrity.
ANSI website

American Printing House for the Blind (APH)

American Printing House for the Blind (APH) is the world's largest non-profit organization creating educational, workplace, and independent living products and services for people who are visually impaired.
APH website

American Sign Language (ASL)

ASL is a language that employs signs made by hand movements, shapes, and placement indicating words, letters, phrases, and ideas; often including facial expressions, postures, and timing. It is the primary language of many North Americans who are deaf or hard of hearing and is also widely used throughout other parts of the world.

Assistive Technology Industry Association (ATIA)

The Assistive Technology Industry Association (ATIA) is a non-profit membership organization of manufacturers, sellers, and providers of technology-based assistive devices and/or services.
ATIA website

Association of American Publishers (AAP)

The Association of American Publishers (AAP) is the largest trade association of publishing companies in the United States. Its members are principally book and academic publishers.
AAP website


Audio, in this context, is a digital form or representation of sound. It is a format that stores, copies, produces sound according to the data in its file(s). Aside from music, audio formats are frequently used for non-visual access to text and images—especially via text-to-speech software.

Audio-Assisted Reading (AAR)

AAR is a technique employed to assist the reading of printed text with pre-recorded speech.

Audio-Supported Reading (ASR)

ASR is a technique employed to support the rapid reading of digital text by displaying portions of text simultaneously with synthesized speech. With a variable highlighting feature the user is able to select the size of the portion (word, sentence, paragraph).

Authorized Entity

Authorized entities are referred to in the Chafee Amendment of 1996 and are defined therein as—"'authorized entity' means a non-profit organization or a governmental agency that has a primary mission to provide specialized services relating to training, education, or adaptive reading or information access needs of blind or other persons with disabilities."

Authorized User

An authorized user is an agent of a coordinating agency with access to the NIMAC database who may download NIMAS-conformant files in accordance with established agreements.


BRF (Digital Braille)

A BRF file type, also known as Braille-ready format, uses Grade II Braille and can be used with common Braille devices or Braille printers.

Blind or Other Persons with Print Disabilities

IDEA includes a definition of students who may be provided with accessible textbooks created with NIMAS files from the NIMAC. That definition used within the legislation is—"Blind or other persons with print disabilities," which means children served under IDEA and who may qualify in accordance with the act entitled "An Act to Provide Books for the Adult Blind," approved March 31, 1931 (2 U.S.C. 135a; 46 Stat. 1487) to receive books and other publications produced in specialized formats." This means that eligible students must qualify under both IDEA and the 1931 Act, which is administered by the Library of Congress.

Braille Authority of North America (BANA)

The Braille Authority of North America (BANA) promotes and facilitates the uses, teaching, and production of Braille.
BANA website


CAST (Center for Applied Special Technology)

CAST is a non-profit organization that works to expand learning opportunities for all individuals, especially those with disabilities, through the research and development of innovative, technology-based educational resources and strategies. The National Center on Accessible Educational Materials for Learning is housed at CAST in Wakefield, MA.
CAST website

Cascading Style Sheet (CSS)

A cascading style sheet (CSS) provides the capacity to separate the layout and style of a web page from the data or information that is its content. Styles such as fonts, font sizes, and margins can be specified in one place. The rendering agent of the web page(s) gathers style elements from this one master list, with identified styles cascading throughout the page(s) or site(s).

Chafee Amendment

A 1996 Copyright Law Amendment allowing "authorized entities to reproduce or distribute copies or phonorecords of previously published nondramatic literary works in specialized formats exclusively for use by blind or other persons with disabilities."

Common Core State Standards

The Common Core State Standards are a U.S. national curriculum standards set designed to provide clear understanding of what K–12 students are expected to learn, specifically to facilitate teaching. The Common Core is intended to be comprehensive and contemporary and intentionally includes consideration of the future in terms of students adult lives via secondary education and employment.

Contracted Braille

Braille characters are much larger than their printed equivalents, and the standard 11" x 11.5" (28 cm x 30 cm) page size used for Braille has room for only 25 lines of 43 characters. To reduce space and to increase potential reading speed, virtually all braille books are transcribed in what is known as Grade II Braille or Contracted Braille, which uses a series of contractions to reduce space and potentially speed the process of reading.

Coordinating Agencies

Coordinating agencies are those state and local educational agencies that have chosen to coordinate with the NIMAC by directing publishers to provide NIMAS-conformant files to the NIMAC.

Coordination Agreement

An agreement between the NIMAC and authorized representatives of educational agencies that have chosen to coordinate with the NIMAC. Authorized representatives must submit a signed coordination agreement to the Repository in order to name Authorized Users and to obtain NIMAS filesets.


DAISY Consortium

The DAISY Consortium was formed for the purpose of establishing the International Standard for the production, exchange, and use of the next generation of Digital Talking Books (DTBs). The DAISY Consortium is made up of organizations throughout the world who serve persons who are blind or print-disabled. The object of the DAISY Consortium is to improve access to all kinds of information for blind and print-disabled people.
DAISY Consortium website


DTBook is an XML element set (dtbook.dtd) that defines markup for the textual content of a DTB (Digital Talking Book).

Department of Justice (DOJ)

The DOJ is part of the federal government of the United States, with the following mission: To enforce the law and defend the interests of the United States according to the law; to ensure public safety against threats foreign and domestic; to provide federal leadership in preventing and controlling crime; to seek just punishment for those guilty of unlawful behavior; and to ensure fair and impartial administration of justice for all Americans
Department of Justice website

Digital Accessible Information System (DAISY)

DAISY refers to a technical standard for producing accessible and navigable multimedia documents. In current practice, these documents are Digital Talking Books (DTBs), digital textbooks, or a combination of synchronized audio and textbooks.

Digital Rights Management (DRM)

Digital rights management systems are authorizing technologies implemented by rights holders and/or publishers to limit the distribution and use of proprietary content. Examples of DRM systems are encryption (securing content as a locked file requiring a hardware or software-based "key" for unlocking), watermarking (the embedding of identifying information on digital files), fingerprinting (the association of specific user data with a particular file or collection of files). DRM systems can employ one or more of these approaches.

Digital Talking Book (DTB)

A Digital Talking Book is envisioned to be, in its fullest implementation, a group of digitally encoded files containing an audio portion recorded in human speech; the full text of the work in electronic form, marked with the tags of a descriptive markup language; and a linking file that synchronizes text and audio portions. In a digital talking book, a reader has random access to book sections via a table of contents. The digitization of books intended for persons with disabilities provides opportunities to increase the quality and availability of information to print-disabled persons.

Digital Text

A book, article, or other published material that can be retrieved by and read via a computer.

Document Type Definition (DTD)

This is a formal definition of a discrete set of XML tags, usually targeted at a particular type of application. For example, the Document Type Definition for the Digital Talking Book would define tags for things one finds in a book, e.g., chapter, paragraph, footnote, jacket, etc.



ePUB (currently version 3) is an open standard maintained by the IDPF as a distribution and interchange format standard for digital publications and documents. It aggregates content components such as audio, XHTML, XML, CSS, images, etc. into one file and is intended as a single e-book format for use in both the production and use of digital publications.


Work performed on a full or part time basis for which an individual is:

  1. Compensated at not less than federal minimum wage requirements or state or local minimum wage law (whichever is higher) and not less than the customary rate paid by the employer for the same or similar work performed by other individuals without disabilities;
  2. At a location where the employee interacts with other persons who are not individuals with disabilities (not including supervisory personnel or individuals who are providing services to such employee) to the same extent that individuals who are not individuals with disabilities and who are in comparable positions interact with other persons; and
  3. Presented, as appropriate, opportunities for advancement that are similar to those for other employees who are not individuals with disabilities and who have similar positions.

Adapted from the Interim Report of the Advisory Committee on Competitive Integrated Employment.


An electronic version of a book that can be retrieved by and read via a computer.


Fair Use

The fair use doctrine, part of U.S. coyright law, states that the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright
Fair Use Copyright information

Free Appropriate Public Education (FAPE)

Special education and related services provided at public expense, under public supervision and direction, and without charge mandated by IDEA.


Grade II Braille/Contracted Braille

Braille characters are much larger than their printed equivalents, and the standard 11" x 11.5" (28 cm x 30 cm) page size used for braille has room for only 25 lines of 43 characters. To reduce space and to increase potential reading speed, virtually all braille books are transcribed in what is known as Grade II Braille or Contracted Braille, which uses a series of contractions to reduce space and potentially speed the process of reading.


Individual Education Program (IEP)

An individual education program (IEP) is a written plan that is individually developed for students identified as having a disability under IDEA. The plan is developed, reviewed, and revised in accordance with IDEA regulations by a duly constituted IEP team of educators, parents, and student (when appropriate). An IEP is based on achievement, assessment, evaluation data and contains the goals that will guide the delivery of special education and related services.

Individuals with Disabilities Education Act (IDEA)

Most recently reauthorized as the Individuals with Disabilities Education Improvement Act in 2004, IDEA is a federal law governing the rights of children with disabilities to receive a free and appropriate public education (FAPE) in what is termed a least restrictive environment (LRE).
IDEA 2004

Instructional Resource Centers for the Blind and Visually Impaired (IRCBVI)

Instructional Resource Centers for the Blind and Visually Impaired (IRCBVI) are nonprofit organizations or governmental agencies that have a primary mission to provide specialized services relating to training, education, or adaptive reading or information access needs of blind or other persons with disabilities in local school districts or special school settings. Additional services are often provided. These centers and their respective representatives are considered authorized entities by the American Printing House for the Blind (APH) for the production and delivery of alternate-format textbooks and instructional materials to students who are blind or have low vision.

International Digital Publishing Forum (IDPF)

The International Digital Publishing Forum (IDPF), formerly known as OeBps, is a trade and standards organization dedicated to the development and promotion of electronic publishing. Oversees development of the EPUB specification.
IDPF website

International Standard Book Number (ISBN)

An ISBN is a unique identifier for a book. An American ISBN agency assigns these individual numbers to books for publishers of all kinds within the U.S. and its territories. An ISBN can be used to identify not only a particular book title or title edition but also its publisher and geographic group of origin.


LMS (Learning Management System)

A learning management system is a software application or suite of applications or a web-based system that provides educational programs and their components such as classes, resources, assessment, tools, and communication, etc.; as well as organizational tools for administration, record-keeping, information sharing, database management, etc., with the intention to manage all parts of a learning process.

LRE (Least Restrictive Environment)

A Least Restrictive Environment (LRE) refers to educational settings and means, in effect, that each identified child with special needs, to the maximum extent possible, shall be educated with children who are not disabled.

LRMI (Learning Resource Metadata Initiative)

The LRMI has developed a common metadata framework for describing and annotating online educational resources with a view to amassing a large body of educational content that is categorized in a consistent manner allowing it to be well organized and more easily accessed by users.

LUA (Limitation-of-Use Agreement)

A legal agreement between authorized users and the NIMAC ensuring that NIMAS filesets will be converted for the exclusive purpose of producing accessible instructional materials for blind or other persons with print disabilities in elementary and secondary schools, as defined in section 674(e)(3) of IDEA.

Once you register through the NIMAC, you will receive an LUA as an attachment to your email confirmation.

More information on how to contac the NIMAC.

Learning Analytics

Learning analytics is the practice of collecting and analyzing a variety of data surrounding learning (students, environment, etc.) with the purpose to improve these. Learning Analytics are also sometimes used for prediction (i.e., of student performance).

Local Education Agency (LEA)

A local education agency (LEA) is a public board of education or other public entity legally authorized for either administrative control or direction of publicly funded schools, including school corporations and state-operated schools.


MathML (Mathematical Markup Language)

An XML-based markup language used to display mathematical content.


Metadata is information that refers to one or more other pieces of information that can exist as separate physical forms (data about data). Any description can be considered metadata. Examples include library catalog information, encoded text file headers, and driver's license data. In the information technology world the term is often used to indicate data which refers to digital resources available across a network.



An NCX file (navigation control file for XML) provides global navigation of a digital work for each structural element. It is part of the DAISY Standard and ePUB.

NIMAS-conformant files

NIMAS-conformant source files are XML files valid to the NIMAS technical specification that can be used to create accessible specialized formats (e.g., braille, audio, digital, large print, etc.) of print-based instructional materials. A complete NIMAS-conformant set of files includes XML content files, a package file, images, and a PDF file of the source content's title page (or whichever page contains ISBN and copyright information).

NIMAS/NIMAC Coordinator (NNC)

A primary contact for NIMAS/NIMAC-related queries and information dissemination. Each state or territory has or will designate one NNC to coordinate these activities within that state or territory.

National Association of State Directors of Special Education (NASDSE)

The National Association of State Directors of Special Education (NASDSE) is a services-focused organization formed to help state education agencies promote and support specially designed instruction and related services for children and youth with disabilities. NASDSE's activities are intended to provide professional support to its members and others interested in special education and to promote the vision that all students can achieve high levels of learning.
NASDSE website

National Information Standards Organization (NISO)

The National Information Standards Organization (NISO), a United States committee organized in conjunction with the internationally known DAISY Consortium, is working on a specification for Digital Talking Books (DTBs). This will serve as the next generation of information technology for persons who are blind and print disabled. At the heart of this specification is an XML DTD that incorporates the elements of structure needed to provide access to information. The specification defines how textual information can be synchronized with digitally recorded human speech through Synchronized Multimedia Integration Language (SMIL), a recommendation of the W3C. The specification identifies six classes of books that have varying amounts of text mixed with audio. Most significantly, one class of book contains only text with no recorded human speech. Access to such information would be through synthetic speech, refreshable braille, or dynamically generated large print.
NISO website

National Instructional Materials Access Center (NIMAC)

The National Instructional Materials Access Center (NIMAC) is a central national repository established at the American Printing House for the Blind (APH) to store and to maintain NIMAS filesets. It features an automated system for allowing publishers to deposit NIMAS-conformant files within the repository. Files are checked to confirm that they are valid NIMAS-conformant files and then cataloged in a web-based database. Those who have been authorized for access have user identifications and passwords. These authorized users may search the NIMAC database and directly download the fileset(s) they need to convert into accessible instructional materials for those students who are in elementary and secondary schools and have qualifying disabilities.
NIMAC website

National Instructional Materials Accessibility Standard (NIMAS)

NIMAS refers to a technical standard used to produce XML-based source files. From these well-structured source files, accessible, student-ready alternate-format versions of textbooks and core materials (e.g., Braille, e-text, Digital Talking Book, large print, etc.) can subsequently be created and distributed to qualified students with print disabilities. NIMAS files are not student-ready versions. IDEA 2004, P.L. 108-446, establishes the NIMAS as a national standard and requires states and local districts to adopt the NIMAS for providing textbooks and instructional materials to students who are blind or print-disabled.

Nemeth Braille Code

Nemeth is a specialized braille code used for conveying mathematical and scientific notation. Its particular strength is in conveying mathematics in a linear way while still remaining compact enough to be practical.


Office of Special Education Programs (OSEP)

The Office of Special Education Programs (OSEP) is maintained by the Office of Special Education and Rehabilitative Services (OSERS) of the U.S. Department of Education. OSEP provides leadership and financial support to assist states and local districts in improving results for infants, toddlers, children, and youth with disabilities (ages birth through 21). OSEP also administers the Individuals with Disabilities Education Act (IDEA).
OSEP website

Office of Special Education and Rehabilitative Services (OSERS)

An office within the U.S. Department of Education, OSERS supports programs that help educate children and youth with disabilities, provides for the rehabilitation of youth and adults with disabilities, and supports research to improve the lives of individuals with disabilities.
OSERS website

Optical Character Recognition (OCR)

OCR software scans images and translates their content into individual elements such as letters and spaces, creating text.

Organic Dysfunction

A reading disability resulting from organic dysfunction is one of the disability categories included in the Library of Congress regulations that establish eligibility for specialized formats under the Chafee Amendment of copyright law. To be eligible, an individual must have a reading disability that is organic in nature (i.e., physically-based) and of sufficient severity to prevent reading regular or standard printed material in a normal manner. The disability must be certified by a competent authority—in this case, a doctor of medicine who may consult with colleagues in associated disciplines.


PARCC (Partnership for Assessment of Readiness for College and Careers)

PARCC is a consortium of 19 states plus the District of Columbia and the U.S. Virgin Islands working together to develop a common set of K–12 assessments in English and Math.
PARCC website

PDF (Portable Document Format)

A universal computer file type used to exchange and view documents on any computer that has the free Adobe Acrobat Reader or free Foxit Reader software installed.

Physical Limitation

In this context, disabilities resulting from physical limitations that prevent an individual from reading or using standard print material is one of the disability categories included in the Library of Congress regulations that establish eligibility for specialized formats under the Chafee Amendment of copyright law. The disability must be certified by a competent authority.

Print Disability

An individual who has a "print disability" is a person who cannot effectively use printed materials because of a disability. With regard to access to instructional materials, IDEA offers a definition that includes reference to individuals who are blind and others: (A) BLIND OR OTHER PERSONS WITH PRINT DISABILITIES—The term 'blind or other persons with print disabilities' means children served under this Act and who may qualify in accordance with the Act entitled 'An Act to provide books for the adult blind', approved March 3, 1931 (2 U.S.C. 135a; 46 Stat. 1487) to receive books and other publications produced in specialized formats.

Print Instructional Materials

IDEA 2004 indicates that the term "print instructional materials" includes printed textbooks and related printed core materials that are written and published primarily for use in elementary school and secondary school instruction and are required by a SEA or LEA for use by students in a classroom.

Prodnote (Producer's Note)

Information added to a DAISY Digital Talking Book or NIMAS fileset by the producing entity that is commonly used to provide descriptions of visual elements such as images, charts, graphs, etc.; supply operating instructions; or describe differences between a print book and its audio version. Traditionally, this has been called a transcriber's note, a reader's note, or an editor's note. Multiple production notes may be used if different versions are needed for different media (i.e., large print, Braille, or print). Some text-to-speech or audio players speak <prodnote> content rather than alternative text.


QIAT (Quality Indicators for Assistive Technology)

The QIAT Community is a nationwide grassroots group that includes hundreds of individuals who provide input into the ongoing process of identifying, disseminating, and implementing a set of widely-applicable Quality Indicators for Assistive Technology Services in school settings that can be used as a tool to support school districts, assistive technology service providers, consumers of accessible technology services, universities, professional developers and policy makers.
QIAT website
QIAT Post Secondary website



Readium is an organization devoted to developing technology to accelerate the adoption of the EPUB3 standard by the digital publishing industry.

Refreshable Braille

Refreshable braille is provided by a display or terminal that is an electronic device which raises dots or pins through holes in a flat surface. Generally, 40 to 80 braille cells are displayed at one time.


Section 188 of WIOA

Section 188 of the Workforce Innovation Opportunity Act prohibits discrimination against people who apply to, participate in, work for, or come into contact with programs and activities of the workforce development system. Specifically, Section 188 prohibits discrimination based on race, color, religion, sex, national origin, age, disability, sexual orientation, or political affiliation or beliefs.

Section 504

Section 504 of the Rehabilitation Act of 1973 is part of a civil rights law that prohibits discrimination against qualified individuals with disabilities. Section 504 regulations require a school district to provide a free appropriate public education (FAPE) to each qualified student with a disability, regardless of the nature or severity of the disability. A written 504 plan is developed to guide the provision of instructional services, including accommodations and modifications, designed to meet a student's individual educational needs as adequately as the needs of nondisabled students are met.

Smarter Balanced Assessment Consortium (SBAC)

The SBAC is a state-led consortium working to develop next-generation assessments that accurately measure student progress toward college- and career-readiness.
SBAC website


Tactile Graphics

Tactile graphics are images designed to be touched rather than seen. They use raised lines and surfaces to provide the outlines of images, graphics, diagrams, maps and more. Tactile graphics are developed primarily to support individuals who are blind or have low vision.

Targeted Technical Assistance (TTA)

TTA involves ongoing work with participating State Education Agencies (SEAs) and collaborating districts (LEAs) to assist with developing, improving and sustaining effective, efficient systems for the provision of specialized formats of print-based instructional materials to students with disabilities. All TTA work is aligned to the Critical Components of Quality Indicators for the Provision of AIM.


Footnote 7 of the RFP that established the National Center for Accessible Education Materials for Learning states:  As used in this priority, ''technology'' means any equipment or interconnected system or subsystem for which the principal function is the creation, conversion, duplication, movement, control, display, switching, interchange, transmission, reception, or broadcast of data or information. It includes, but is not limited to, electronic content; telecommunication products; computers and ancillary equipment; software; information kiosks; transaction machines; videos; information technology services; and multifunction office machines that copy, scan, and fax documents.

Text Encoding Initiative (TEI)

Initially launched in 1987, the TEI is an international and interdisciplinary standard that helps libraries, museums, publishers, and individual scholars represent all kinds of literary and linguistic texts for online research and teaching using an encoding scheme that is maximally expressive and minimally obsolescent.
Text Encoding Initiative website

Text-to-Speech (TTS)

Text-to-speech or speech synthesis is the artificial production of human speech and is generally accomplished with special software and/or hardware. The quality of various speech generation engines can vary considerably. Some voices sound almost human while others sound more primitive and robotic. The robotic-sounding voices are considered desirable for achieving high rates of "reading" speed.


Uncontracted Braille

Uncontracted braille provides a character-by-character transcription of a source text and is sometimes considered best for teaching young children braille. For experienced readers, it does not provide the space saving (and therefore reading speed and efficiency) of contracted braille.

Universal Design for Learning (UDL)

Universal Design for Learning (UDL) is a framework of learning and teaching based on neuroanatomy and functional neuroimaging research techniques. UDL resists a one-size-fits-all approach to education and posits instead that teachers, educators, and instructional materials should effectively respond to individual differences inherent within a learning environment. Across learning goals, methods, materials, and assessments, Universal Design for Learning encourages offering—

  • Multiple means of representation to give learners various ways of acquiring information and knowledge,
  • Multiple means of expression to provide learners alternatives for demonstrating what they know, and
  • Multiple means of engagement to tap into learners' interests, challenge them appropriately, and motivate them to learn.

Using UDL principles in a classroom removes obstacles to curriculum access and provides students with alternative methods to demonstrate what they know. It acknowledges that there is more than one way to learn and respects individual learning style differences.
CAST's About UDL
UDL Guidelines

Universally Designed Technologies

Products and services that are designed and delivered to be usable by people with the widest possible range of functional capabilities, which include products and services that are directly accessible (without requiring assistive technologies) and products and services that are interoperable with assistive technologies. (20 U.S.C. §1401(35)(IDEA); 20 U.S.C. §1003(23)(HEOA), both referencing the Assistive Technology Act of 1998, as amended, 29 U.S.C. §3002).


Video Description

Video description or audio description refers to the inclusion of verbal or auditory description(s) of on-screen visuals intended to describe important visual details that are not contained or that cannot be understood from the main audio output alone. They are of particular value to individuals who are blind.
Audio description from WebAIM


W3C (World Wide Web Consortium)

The W3C is an international consortium founded in 1994 to promote the evolution and ensure the interoperability of the World Wide Web. Working with the global community, the W3C produces specifications and reference software for free use around the world. The W3C established the Web Accessibility Initiative (WAI) in 1997. Changing the Web's underlying protocols, applications and, most importantly, the way content is developed, can significantly improve access to the Web by people with disabilities. The WAI has working groups developing comprehensive and unified sets of accessibility guidelines for content accessibility, browser accessibility, and authoring tool accessibility.
W3C website


XML (EXtensible Markup Language)

XML is a universal format for structured documents and data. It is a set of rules, guidelines, and conventions for designing text formats for data in a way that produces files that are easy to generate and read (by a computer), are unambiguous, and avoid common pitfalls such as lack of extensibility, lack of support for internationalization/localization, and platform-dependency. Like HTML, XML makes use of elements and attributes, but while HTML specifies what each means (and often how content will display in a browser), XML uses tags et al. only to delimit pieces of data and leaves the interpretation of that data completely to the application that reads it. The separation of content and its presentation is a primary advantage of XML.