is avi the same as xvid?

[RaymondLovesToWrite]

are they? or are they different?

[StevenJPemberton]

No, they're not the same. Xvid is a codec; AVI is a container format.

A codec (short for coder-decoder) is a piece of software that understands how individual frames of video are represented. There are many ways of doing this, and they're the subject of endless debate on Internet forums about which is best.

A container format packages up the frames that have been encoded with a codec, allows for a soundtrack, allows for subtitles (possibly in more than one language) and all sorts of other information. A program that plays or edits video files knows how to read the container format, but leaves it up to the codec to determine what each frame looks like when the user plays the file. If someone comes up with a better way to compress video frames, they write a codec for it, and it just plugs in to the container format, so that all the playing and editing programs can handle the new format automatically (as long as the user has a copy of the right codec).

Horrible analogy - a container format is like specifying that you want to store liquid in pint bottles, and the bottles have to be stored in crates. So you would specify the dimensions of the bottles, maybe the materials they could be made of, and the dimensions of the crates. But you don't say anything about what goes in the bottles. It could be water, milk, beer - anything. That's the job of the codec. One codec might say "beer made to this recipe". Another codec might say "pasteurised semi-skimmed milk". You can store both liquids in the same bottles, and the bottles in the same crates.

[JesseF]

.avi is a file extension. xvid is a compression format.

.avi can be used to hold video of almost any compression format. Including xvid, Dvix, RAW, ...ect.

However generally .avi is an uncompressed video format meaning that each minute is several gigabytes. That is the format used by many video editing programs.
The xvid compression format is a lossy compression format which means that the quality is drastically reduced over the original footage. Though you can have a .avi file that has been compressed with xvid, such as most pirated movies, they are not the uncompressed lossless .avi that editors use when manipulating video.

Also something to note, the uncompressed avi format was developed by microsoft and is now an open format while xvid was developed as a free open video codec/compressor. The most similar thing to xvid out there is dvix which is similar in ability to reduce quality and decrease filesize drasticly, however dvix is not a free encoder to use to encode video with.

[soupfine]

No

Xvid is an open-source MPEG-4 ASP video codec. It is not a format. There is no such thing as "xvid video" – it is MPEG-4 ASP video. It may be stored in the avi container.

avi is a container...a format for packaging data like audio and video.

[SchoenbergPfitzerglyehud]

Great answers from Wiki:
Aviv (literally "Spring Hill") was chosen in 1910 out of many suggestions, including "Herzliya". Tel Aviv is the Hebrew title of Theodor Herzl's book Altneuland ("Old New Land"), translated from German by Nahum Sokolow. Sokolow took the name from Ezekiel 3:15: "Then I came to them of the captivity at Tel Aviv, that lived by the river Chebar, and to where they lived; and I sat there overwhelmed among them seven days."[23] This name was found fitting as it embraced the idea of the renaissance of the ancient Jewish homeland. Aviv is Hebrew for "spring", symbolizing renewal, and tel is an archaeological site that reveals layers of civilization built one over the other.[24] Theories vary about the etymology of Jaffa or Yafo in Hebrew. Some believe that the name derives from yafah or yofi, Hebrew for "beautiful" or "beauty". Another tradition is that Japheth, son of Noah, founded the city and that it was named for him. The name is also transliterated as Tel-Abib in the King James Bible.

[GeekPowerXD]

They are the same, more people use AVI because it's more popular and most operating systems can read the file format without any other programs. The quality is also improved and the file size is lowered buy a few units of kb.