artifacting The occurrence of unwanted visual distortions that appear in a video image. A common side effect of compressing at lower bit rates.
bandwidth A measure of the capacity of a data line. Video is transferred most efficiently on a high-bandwidth connection (also called broadband.)
bitrate The number of bits per second used by a particular piece of media. Higher bitrates generally translate to higher quality, but some codecs are more efficient than others.
BitTorrent A peer-to-peer protocol that makes clients double as servers, allowing files being shared to be downloaded faster by peers who join the Torrent.
blog (also weblog) A log or journal published on the Web, which often accompanies podcasts and vidcasts.
codec (compressor/decompressor) A piece of software that compresses audio or video. The same codec also plays back the compressed media.
deinterlace To convert interlaced video into progressively-scanned video, for use with computers.
DSL Digital Subscriber Line. A way of sending digital data over regular copper telephone lines at high speed.
full-motion video A standard for video playback on a computer; refers to smooth-flowing, full-color video at 30 frames per second, regardless of the screen resolution.
interlaced video Process of scanning frames in two passes, each painting every other line on the screen. NTSC video is interlaced; most computers produce a noninterlaced (also known as progressive) video.
ISP (Internet Service Provider) A company that provides access to the Internet.
MPEG-1 A video compression standard set by the Moving Picture Experts Group. It encodes only those elements of a video image that actually change from frame to frame.
MPEG-2 The highest quality video compression currently available. MPEG-2 is less blocky than MPEG-1 and is used in DVDs and DBS satellite TV systems.
MPEG-4 A recent data compression format that can get better quality out of a given amount of bandwidth. MPEG-4 can compress a feature film onto a CD-ROM disc with VHS quality.
news aggregator A program that can receive RSS feeds. The Firefox and Opera Web browsers include news aggregation functions, and many specialized RSS feed aggregators are available for download. Some programs offer special aggregation functions, such as iTunes, which includes automatic podcast download capabilities.
podcast The delivery of an audio program to a computer via an RSS feed which sends new files automatically to the user's computer.
RSS (Really Simple Syndication) A technology that allows you to subscribe to a Web site that provides periodically updated information automatically to your computer. To receive these feeds you must an aggregator.
streaming media Live or recorded audio or video delivered from a server directly to a client with buffering only, so the media is not saved.
Vidcast (-ed, -ing, -er) The delivery of a broadcast quality video program to a computer via RSS. Viewing is intended for a television screen but can also be viewed on computer monitors and portable video devices.
Video delivered later (VDL) A concept by which customized video programming is selected by a user to be delivered and stored when bandwidth congestion and usage are lightest.
VOD Abbreviation for Video on Demand. Usually only heard in the context of delivering full-frame, full-motion video to a television; since most video on the Internet is provided on-demand.
Web syndication One goal of RSS, which is to allow Web sites to carry stories posted on other Web sites.
Webcasting The act of delivering a live media stream over the Web.
Webinar A seminar delivered over the Web that allows participation.
XML (eXtensible Markup Language) The underlying language used by RSS. Generally easier for humans to read than other markup languages like HTML.
