Trying to understand wrapper vs codec

[brassplyer]

I've seen mentions of wrapper vs codec. Looking at the various options under Super choosing options like mov , avi, mp4, I see some of them have the same options under codec and audio.

So, if you have a mov file, an avi file and an mp4 file that all have for example, an H.264 codec and AAC audio, does this mean they're all essentially the same file?

If so, why is there more than one "wrapper"? What's the difference? If you don't want to re-invent the wheel and know a good resource that really spells it out that would be fine.

Thanks for all input.

[Soopafresh]

Think of a wrapper (or container as it's also called) as an envelope in which you place your audio and video. The codec of that video might be Xvid, h264, DivX, or many other types. The audio might be MP3, AAC, WAV, AC3, etc.

So, you could put h264 and aac into an MP4, AVI, MKV, MTS, or MOV container. Or, you could put DivX and Mp3 into an MP4 or AVI container. Certain containers are required by certain hardware players or by certain applications - A DVD player which also plays DivX typically requires an AVI container with DivX or Xvid video and MP3 or AC3 audio. iPods are particular to h264 and AAC inside an MP4 container.

All containers have pluses and minuses to them. One isn't necessarily better than another , just more compatible with an editor or hardware player.