MP4 also known as MPEG-4 AVC (Advanced Video Coding) is a compressed multimedia container format which simply means it can hold both video and audio files in smaller file size without major loss in quality. It is pretty much similar to mp3 except compression is much more complex. MP4 was developed by Moving Picture Experts Group (MPEG) and was based on Apple's QuickTime container format.
You can convert your own videos to mp4 format. Go to MP4 Converters section to convert your own videos to MP4 format, if you're looking for quality videos and movies to download head over to MP4 Videos section. You need an MP4 Player in order to play any mp4 files in your computer.
MP4 files basically have an .mp4 or .mp4a extension. Audio-only MP4 files generally have a .m4a extension. The .mp4 extenstion is use by iTunes Store for DRM copy which is protected content and an .mp4a is for DRM free and therefore the files are unprotected. 3G mobile phones use 3GP format which are simplified version of MPEG-4.
Compatible software that plays MP4 format includes QuickTime Player, iTunes, Winamp, RealPlayer, Nero Media Player, Media Player Classic, Mplayer, foobar2000, KSP Sound Player, VLC media player and Avidemuxiola.
Playstation Portable (PSP), Playstation 3, Microsoft Zune are some known hardware that support MP4 playback.
There is quite a few MP4 converters outthere, for converting any of your file(s) format to MP4 format I personally recommend ImTOO PSP Video Converter or Xilisoft PSP Video Converter. If you're looking to convert your DVD movies to MP4 format Avex DVD to PSP Converter would be the best. There is also PSP Movie Creator where you can create your own movies in easy steps.
Any of the converters above should work perfectly on your PSP or any other hardware that support mp4 playback.
You can download and watch any of your favorite movies and TV shows to your PSP. I have tried many PSP movie download websites but PSP Blender and All PSP Games I would say is the best in the industry. There is also PSP Wizard and Unlimited PSP Movies both is great as well.
If you're looking to convert your own videos to mp4 format this can easily be done using a MP4 Converter.