Confused about mp4. Container or codec?

[vid83]

I have a hard time wrapping my head around the idea of containers and codecs.

I work with photo editing and everything is straightfoward. JPEG is JPEG. But in video, it is so much more complicated. You have containers and you have codecs.

I read that mp4 and mpeg4 were the same.

I thought mp4 was a container. But when I was wanting to convert a video in SUPER, I noticed that MP4 was under "Select the Output Container" and saw MPEG-4 under "Select the Output Video Codec". But I thought mp4 was a container, not a codec.

Is mp4 a container and a codec? Why is it listed as MP4 under "container" and MPEG-4 under "Codec"? Why not MP4 under both or MPEG-4 under both?

[jagabo]

MPEG 4 specifies several things including the MP4 container*, MPEG 4 Part 2 encoding (Divx, Xvid, etc.), and MPEG 4 Part 10 encoding (h.264, AVC, etc.). People use the term MP4 and MPEG 4 loosely.

* The term "container" refers to the way data is organized within the file, regardless of what compression schemes are used.