Must you have a codec to play MPEG-1, AVI, MPEG2, ETCETERA?

[DrZombie]

I am a little confused about the differences between codecs and just plain software players. What is the difference between a codec and a player? Let's use Windows Media Player as an example. People talk about it as it's not a codec. But, DivX is talked like it is a codec and a player. DO YOU ABSOLUTELY HAVE TO HAVE A CODEC IN ORDER TO PLAY MPEG-1 and MPEG-2 files? I am not understanding the differences. I know that codecs are compressors/decompressors. Can someone help explain?

[Anonymoususer]

Well...to my knowledge...PLAYERS are supossed to play Video/Audio files..BUT some files are ENCODED using..certain Decompressors etc...SOO...for SOME files you HAVE to have those Codecs installed for THAT file to work correctly...Codecs are like little parts that run a player..so if you don't have that part installed it won't work right...results could be jerky video/ syncing problems.....I hope I could explain this for you....hope you understand....