01In plain English
A codec squeezes video or audio into a manageable file size and unpacks it again for playback. The file type, such as MP4 or MOV, is the container; the codec is what is inside. Some codecs are small and hard to edit, others are large and smooth to edit.
02Why it matters when you are choosing
The codec decides whether an editor can open your camera footage, how smoothly it plays while you edit, and which formats you can deliver.
03What to check
Ask the vendor
Check that the editor supports the codecs your camera records and the ones your clients or platforms ask for.