Glossary
AAC-(advanced audio coding) a lossy digital audion compression scheme. Redundancies in the code are eliminated. It is currently used as the default iTunes codec. It is also referred to as MPEG4 AAC.AIFF-(audio interchange file format) used for storing sound on a computer. Is most commonly used on Apple computers.
AVI-(audio video interleave) contains audio and video data for simultaneous playback.
Beta testing- testing to check the correctness and quality of developed material (like with a computer software program). Makes the material available to selected groups for review.
Bit rate- the number of bits of audio, video, or data that are expressed per unit of time. Bit rate is usually measured in kilobits per second (Kbps) or megabits per seconds (Mbps).
Codec- device or program that is capable of performing encoding and decoding in a digital data stream or signal. It is a combination of coder-decoder. It is often used invideoconferencing and video streaming. Most codecs are lossy in order to get a smaller file size.
Compression- encoding information using fewer bits. It can be lossless or lossy. The more a file is compressed the lower its file size and quality.
Encoding- formatting information from one file type to another.
Encryption- obscuring information to make it unreadable without special knowledge. Used to protect communication.
FLV-(Flash Video Format) It has the ability to be embedded in web pages so the video can be viewed in the browser.
GIF-(graphic interchange format) lossless data compression file format. It is used frequently for short videos in web browsers and web page logo images.
JPEG-(Joint Photographic Experts Group) common file format for compressing photo files. It provides lossy compression.
MP3- lossy compression digital audio encoding format. Files can be compressed at different bit rates, but there is a trade off between sound quality and file size.
MPEG4-(Moving Picture Experts Group) a standard for compressing audio and video files. It can support audio, video, 3D objects, and text files. Files can be compressed at different rates, but there is a trade off between quality and file size.
PDF-(Portable Document Format) an adobe file format that can be read by any software.
PNG-(Portable network graphics) pronounced ping. It has lossless compression for images and was created to replace the GIF file format.
Podcast- a multimedia file distributed over the internet using syndication feeds, for playback on mobile devices and personal computers. the word podcast is a combination of the words broadcast and iPod.
RSS-(really simple syndication) an XML based system that allows users to subscribe to web pages, blogs, podcasts,etc.
Streaming files- media that can be watched as it is being delivered over the internet.
Suscription feed- alows users to have files such as podcasts or other audio or video automatically downloaded to their computer through the use of RSS.
TIFF-(tagged image file format) for storing high color depth images. It uses tags in the file headers and can be used for multiple images. applications use the tags to accept or ignore certain parts of the file. TIFF is a lossless compression format.
Unicode- an industry standard to universally show text and symbols from all of the writing systems and to allow them to be manipulated by computers. Unicode is used in many new technologies, such as XML.
W3C-(World Wide Web consortium) develop protocols and guidelines for the internet.
WAV-(waveform audio format) standard audio storing method for Microsoft. Normally contains uncompressed audio files. File size is limited to under 4GB.
Web feed- data format used for frequently updated content on web pages, like news feeds or podcasts.
WMV-(Windows media video) video codec created by Microsoft.
XML-(Extensible Markup Language) a data description markup language that allows for sharing data across different systems over the internet. XML is also used for file storage.