Before we get started, let’s avoid any confusion. There are two meanings to the term “File System” in the wonderful world of computing: First, there is the system of files and the directory structure that all of your data is stored in. Second, is the format scheme that is used to write data on mass storage devices like hard drives and SSD’s. We are going to be talking about the first kind of file system here because the average user will interact with his or her file system every time they use a computer, the format that data is written in on their storage devices is usually of little concern to them. The many different file systems that can be used on storage is really only interesting to hardware geeks and is best saved for another discussion. Now that that’s cleared up, we can press on.
Back to Computing 101
A computer file is a block of discrete information generated by a computer program and saved to a long-term storage device for retrieval later. In Linux, everything is a file. Even the devices hooked to your computer are represented as files. The novice computer user can usually identify some files because there are many standard formats. Files with the .mp3 extension are automatically associated with audio that is encoded in mp3 format, for instance. (Read the rest at Freedom Penguin)