File system is a system where data is organized in files on storage devices.
Computers use operating system to operate the system, where file system is used to organize our data. So you understand file system is used to organize our data in the file.
The computer has lots of storage devices (like hard disk, pen drive, CD, DVD, Floppy disk, etc.) and each device uses a different method to write data physically on them. For example, Hard disk store data electromagnetically similarly CD/DVD device store data optically through a laser beam and pen drive also use a different method to store data.
So my point is how the computer knows to read or write data on those devices because every device uses a different method to store data. For example, If I store some data on pen drive so how other computers understand how to read this data. So to solve this we use file system.
File system gives us a structure, which helps to organize data so other computers also understand. It knows the location of particular data inside a storage device.
Let see another simple example, when you see in your computer, you see many folders and folder contains other subfolders or files like word file, excel file, image file, video file, etc. So in computer, data is organized in hierarchical structure (like C: /Folder1/ Folder2/ File1.txt). This is possible because of file system.
In storage devices, File system separates data into pieces and gives name each piece, so the data is easily isolated and identified.
The file system is a collection of methods and data structures used by the OS to organize and keep track of the files on your disk. Among other information, these data structures contain mappings between the logical name/location in the hierarchical structure and their location on the physical disk.
Windows File System
Every operating system has different file system. Windows OS is the most popular and most used OS today’s date.