Convert a Movie For The iPod (or iPhone)?

I have a few movies in my computer and I'd like to convert them to iPod format so I can watch in the airport. And maybe to iPhone format too.
I have no idea what format I have to convert the movies to. Is there such a thing as an iPod format? Can the iPod play regular PC movie files like avi?
And how many movies will I be able to have in my iPod?
Please help.

In order to play movies in the iPod or iPhone, download AVS Video Converter. It is a very useful application that allows you to convert video files between multiple formats.
Then use it to convert your movies into MPEG-4 format, the file type is MOV. Search for it at download.com
If you're using a PC I think that you need to also download and install Quicktime to convert the movies but I'm not sure.
The conversion process will take some time, it will depend on the size of the original movie.
Once the conversion finishes, transfer the movie to your iPod or iPhone and that's it.

iphone 4 supported H.246, MPEG-4, Motion JPEG. ipod supported MPEG-4, H.264. But you didn't provide more information of you movies, you can use video converter like ifunia iphone and ipod video converter to convert it.