How to write to PCM and Wav Files [closed]

Can someone explain to me how do you write to Wav files and PCM files ?? What do I need to know? Do I need to know the size and etc?

Sorry if its a stupid question, I know how to write to text files but I have just been stucked with Wav and Pcm right now for a couple of days and I just don't get it and feel kinda dumb.