The file management system is used to maintain file maintenance operations. A file management system is made to manage individual or group files, such as unique office records and documents, however, it has limited functionality. This paper emphasizes on study of various existing file system. Here, the file system of OS uses a balanced tree file system in which it will implement various priority systems like arranging file system on a scale of 1 to 5 where 1 has the most priority. File system is very important for every operating system. It is used to systematically store the information in the secondary memory. File name is very important part as it helps in distinguish easily our from other files and access the information from secondary memory easily. There are basically two parts of file naming first is name and other is part is the extension which is separated by “.”. Some types of extensions are.doc,.exe,.jpg,.c,.java, etc. Various operations can be performed on file system, some of the operations are like creating a file for this operation there should be free space available in the secondary memory