Cs Basics File Extensions MP3 & MP4

CS Basics: File extensions 3:48
Files & File Systems: Crash Course Computer Science #20 12:03
Computer Fundamentals - File Extensions & Types - How to Show & Change Files Extension in Windows 10 4:28
Every File Format Explained in 16 Minutes 16:30
Computer Basics: What is a Windows File Extension? 2:38
All Windows System File Extensions Explained 2:21