In most operating systems, a file must have a unique name within a given file directory. However, while creating a filename, certain characters are considered illegal, and hence cannot be used. A filename is comprised of a name with a suffix, which is also known as a file extension. The file extension is two to four characters following the period in the complete filename. The file extension helps in identifying the type of file, file format and the attributes associated with the file.

Most modern computer systems provide security or protection measures against file corruption or damage. The data contained in the files could range from system-generated information to user-specified information. File management is done with the help of operating systems, third-party tools or done manually at times with the help of the user.

The basic operations that can be performed on a file are:

• Creation of a new file
• Modification of data or file attributes
• Reading of data from the file
• Opening the file in order to make the contents available to other programs
• Writing data to the file
• Closing or terminating a file operation

In order to read or modify data in a file, specific software associated with the file extension is needed.