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Webcasts and Web Conferencing

For additional related resources, see also CAST's UDL On Campus web site.


This guide discusses two multimedia tools, webcasts and web conferencing, that can enhance online learning while considering the principles of Universal Design for Learning (UDL). Webcasts and web conferencing are two of the most utilized delivery services for online learning in postsecondary education. Both of these tools offer instructors options for presenting content and engaging students.

On this page, you will find—

  • an introduction to webcasts and web conferencing
  • features of each tool and considerations for selection
  • terms related to accessible media
  • resources for learning more about these tools
  Webcast Web Conferencing
Definition A pre-recorded or live presentation that is broadcasted to many viewers and listeners across the web. A form of real-time or live communication in which multiple participants share in the event via the web.
Purpose Share content and inform participants Present content, engage participants in chat, conduct demonstrations
Features Typically includes video, audio, and captions Screen share, video, audio, voice or text-based chat, whiteboard capabilities, captioning

A webcast is typically a better choice when a lecture or presentation is pre-recorded and the purpose is to inform students of content. Web conferencing is used primarily for live presentations (which may include pre-recorded media) and when instructors wish to enable student interaction. Such events are typically facilitated live by the instructor. Student interaction can occur through voice/video chat, or text-based messaging. Web conferences are also sometimes referred to as webinars.


When selecting which methods you'd like to use for instruction, consider the following questions:

  1. What is the goal? Do I want to inform students or promote a discussion?
  2. What is the content? Is this new material or is this a review?
  3. What other methods and supplemental methods am I using? Do I need to support this webcast or web conference?
  4. What resources do I currently have? What resources do I need?
  5. Who are my learners? Am I considering learner variability?

The learning sciences demonstrate that individuals are highly variable, and that this natural variability is systematic in terms of the way that people represent information, in the way that they engage with learning materials and tasks, and in the way they approach learning tasks and show what they know. Thus, the challenge in developing learning environments is to design not for the “average” learner—there is no such person—but to design flexible approaches to teaching and learning that accommodate human variability and optimize learning opportunities for all. For instance, an instructor could deliver the same content using multiple representations in using infographic, text, and audio. Similarly, students may have the option to demonstrate their knowledge by using Voicethread, a web-based application for interactive media-based collaboration commonly used in postsecondary settings, or creating a text-based document (e.g., essay, blog, slideshow). Gather more information more about learner variability in this video.


A webcast is a media presentation that uses streaming media technology to broadcast content live or on demand through the Internet to many simultaneous learners. It is intended for large audiences. Webcasts that use live streaming are broadcasting content as it occurs in real time, using a camera to capture the media, an encoder to digitize the media, a media publisher to organize it, and a content delivery network that distributes it to its intended audience(s).

  Webcast Features
Visuals and Audio
  • Live or pre-recorded presentations
  • Use of slide-based content
  • Inserted video or computer screen captures
  • Live computer demonstrations
  • Remote live audio
  • Interactivity
  • Chat box for audience Q&A

Why use webcasts?

Webcasts are increasingly becoming an important part of higher education, often in the form of massive open online courses, or MOOCs. For example, you are a professor who teaches a popular course on philosophy. You want to broadcast pre-recorded lectures so that you can reach the widest possible group of students. This is your first time teaching a course this way. When deciding whether or not you want to go the webcast route, it is critical to consider who you intend to view your content. This seems like a simple question but it actually requires flexibility.

Cisco wrote a white paper based on research on the impact of broadcast and streaming media and education. The table below shows some of the uses of streaming media in education.

Type of Instruction Example
Basic Instruction In foreign language classes, history, and geography lessons where students can bring a subject to life, stimulate their ability to recall facts and events, and experience places they wouldn’t otherwise experience.
Advanced Instruction In science subjects like physics, mathematics, astronomy, and biology allowing students to expand their understanding of complex concepts by strengthening the links between abstract ideas and practical applications.
Classroom Enrichment Video gives students the opportunity to travel to remote places outside the classroom walls without leaving school.
Accelerated Learning One-way streaming blended with other online methods of communicating is one of several ways of ensuring that learners can take the college-level courses they need.
Distance Education To make courses, lectures, and faculty accessible to populations in remote areas and also to students with disabilities or with physical impairments.
Global Student Collaboration Video technologies can help students connect with peers located in different campuses and in different countries so that they can interact with different cultures, exchanging information and learning from each other.
Communications Video can also be used to stream instructional/informational or entertainment related content at campus public areas such as cafeterias, auditoriums, and stadiums.
Professional Development Using video technologies has proven helpful for primary and secondary in training teachers when sharing resources, exchanging ideas, recording and evaluating themselves, and taking full advantage of professional development opportunities they might otherwise miss.

Source: Greenberg, A. D. & Zanetis, J. (2012). The impact of broadcast and streaming video in education.
A report commissioned by Cisco Systems, Inc., San Jose, CA. Retrieved from

How do I know which webcast platform to use?

It is critical to ask questions about accessibility features when choosing a webcast platform to consider the importance of learner variability when developing curriculum for online learning. When educational entities are aware of the strengths and limitations of certain features, they can be better prepared in their planning process by utilizing features that do not exclude learners.

Accessibility Concerns Questions to Ask
Captions Does the webcast product or service support captioning for participants? If so, can the captioning window be moved and re-sized? Can the font size or color of the caption text be changed?
Keyboard Are all features accessible by the keyboard alone? Some users are unable to use a mouse.
Screen Readers Are all the features compatible with screen readers? Some products, even if accessible by keyboard, do not provide screen readers with essential information about interface components. Therefore, screen reader users may be able to navigate through the webcast environment, but they'll be completely lost without dependable audible feedback. If the webcast environment is generally accessible to screen reader users, how are these users notified when content changes dynamically? For example, if the instructor advances to the next slide, or if a participant receives a private chat message from another participant, how is the screen reader user made aware of this information?
Color Are there features that communicate information exclusively using color? If so, these features will be inaccessible to users who are unable to perceive color differences. For example, some webcast products include audience seating charts in which audience members can change the color of their seats to send messages to the instructor such as "Slow down" or "Speak up". If the instructor is color blind, they will be not receiving this important feedback.
Customization Is the webcast environment customizable? Given the complexity of many webcast environments, participants with cognitive or learning disabilities can become easily distracted and may benefit from closing windows or disabling features. Participants using screen magnification software might also benefit from being able to rearrange their environment for optimum display on an enlarged screen.

Source: University of Washington Access IT. DO-IT Factsheet #1205.

The Web Content Accessibility Guidelines 2.0 outline guidelines on web accessibility. In the context of streaming media, Guideline 1.2 on time-based media is particularly relevant.

How can I provide access?

Including accessible materials such as transcripts, audio files, images, and downloadable text documents plays an important part in providing access to multiple means of representation and engagement with learners as they interpret and engage with the streaming media.

Providing access to captioning is important because it ensures access to real-time information for learners who need visual and text support. A pre-recorded lecture that is available for viewing should ideally contain open or closed captions embedded in the video. A live streamed presentation delivered in real time will need support from a professional CART (Communication Access Real Time Translation) provider. CAST has a listing of recommended additional resources on captioning and transcription.

The 21st Century Telecommunications and Video Accessibility Act stipulates how video content needs to be accessible on the Internet. It was signed into law in October 2010.

Wikipedia’s editors maintain a comprehensive list of streaming media systems as well as a technical comparison of these systems.

Web Conferencing

Web conferencing can be an excellent method to engage learners from multiple remote locations. Typically, students watch a live presentation while they interact with the instructor and their classmates using text-based messaging, and/or voice/video chat. Web conferences are designed to be more interactive than a webcast and allow more options for instruction. A telephone line may be used for communication while other participants are viewing the presentation using screen share technology. Some web conferencing services allow for all communication to take place over the internet.

  Possible Web Conferencing Features
  • Screen sharing (e.g., slides, web pages)
  • Whiteboard capabilities
  • Play live or pre-recorded video
  • Annotate images and documents
  • Text chat
  • Webcam capabilities
  • Real-time audio communication
  • User polls and surveys

Why use web conferencing?

You are teaching a nursing course online that focuses on cardiovascular disease. One unit in particular features diagnosis and treatment. Up to this point, your students have watched a number of webcasts of pre-recorded lectures that have outlined these topics. Now you are interested in answering their questions, promoting more critical thinking, and inspiring peer-to-peer learning. You design a presentation that includes a number of case studies featuring different patients with types of cardiovascular disease. You choose to facilitate a web conference so that you and your students can use video chat along with your presentation, share documents, and annotate images. As you are planning your web conference, it is critical to think about accessibility.

A web conference that lacks certain features would be inaccessible to a number of students. Those students who are deaf or hard of hearing would not be able to access the audio components of the voice/video chat and presentation. Adding captioning to your audio would not only provide accessibility to these students, but to other students who benefit from text, including those who have auditory processing difficulties, attention difficulties, and those who are English language learners. The W3C Web Accessibility Initiative provides detailed requirements and techniques for meeting accessibility.

How do I add captioning to a live web conference?

Adding captioning to a live event is different from adding captions to a pre-recorded presentation. Web conferencing requires real-time captioning and a captioner is typically hired from an outside source. For instance, the Media Access Group at WGBH provides caption services for pre-recorded videos, as well as real-time captions for live web conferencing.

There are several services that offer web conferencing. Features and pricing vary by vendor. While some vendors offer a monthly flat fee, other vendors utilize a model that charges per user per minute. Some free services exist, such as Google+ Hangout, which offers video chat and some capability for sharing video, images, and documents.

When selecting a product, it is important to review the options for accessibility; however, given the number of services in the market, it can be daunting to research each product. In 2009, the Voluntary Product Accessibility Template (VPAT) was created by the Information Technology Industry Council (ITI) in order to standardized the way in which developers could report on their compliance with Section 508 requirements.1 A VPAT is specific to individual products and, ideally, allows consumers to make informed decisions when considering accessibility for students with disabilities. Below are links to the VPATs for various web conferencing products:

Adobe Connect VPAT

ReadyTalk VPAT

Cisco WebEX VPAT

iLinc VPAT

Blackboard Collaborate VPAT

More information on VPATs, Section 508 standards, and accessibility can be found in the in the associated white paper from the The Center on Online Learning and Students with Disabilities, a partnership of researchers at the University of Kansas Center for Research on Learning, the National Association of State Directors of Special Education, and CAST.

1Section 508 is the amendment to the Rehabilitation Act that requires barriers to be removed from information technology so that web applications, web pages, and attached files may be accessible to those with disabilities.


This page provides a list of selected resources for streaming media systems, web conferencing software, and captioning and transcription.

Streaming Media Systems

Listing of Streaming Media Systems
A list of available streaming media systems and descriptions.

Comparison of Streaming Media Systems
A side-by-side comparison of streaming media systems that includes features and costs.

Comparison of Web Conferencing Software

Comparison of Web Conferencing Software
A side-by-side comparison of available web conferencing software.

Captions and Transcriptions Resources

Companies and Services

Provides captioning services for streaming media.

A tool for crowdsourcing captions and subtitles for existing online media.

Caption Match
Provides connection between those seeking captioning services and captionists.

Described and Captioned Media Program
A free-loan library of described and captioned media.

DCMP’s Captioning Key
A manual of best practices in captioning.

Provides services including media solutions for accessible webcasts, presentations, and streaming.

Media Access Generator (MAGpie)
A free caption and audio authoring tool for making accessible media.

National Court Reporters Association
A resource on real-time captioning, with information on where to find CART providers.

Provides real-time text communication.

Provides closed captions and subtitles.

WGBH Media Access Group
Provides access to media for people with disabilities.

Support for Adobe Connect
Provides captioning for web conferencing through Adobe Connect.

Support for Streaming Media
Provides captioning for real-time and pre-recorded media.

Wowza Media Server
Provides closed captioning for Wowza Media player.

Organizations and Blogs

Audio Accessibility
More resources on captioning and audio accessibility.

CCAC Captioning
An educational and advocacy group for inclusive captioning.

COAT Access
An advocacy group that focuses on accessible and usable technology.

Last Updated: 07/14/2014

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