Disk Formatting

Disk formatting is the process of preparing a data storage device such as a hard disk drive, solid-state drive, floppy disk or USB flash drive for initial use. In some cases, the formatting operation may also create one or more new file systems. The formatting process that performs basic medium preparation is often referred to as "low-level formatting". The term "high-level formatting" most often refers to the process of generating a new file system. In certain operation systems (e.g., Microsoft Windows), the two processes are combined and the term "format" is understood to mean an operation in which a new disk medium is fully prepared to store files. Illustrated to the right are the prompts and diagnostics printed by MS-DOS's FORMAT.COM utility as a hard drive is being formatted.

As a general rule, formatting a disk leaves most if not all existing data on the disk medium; some or most of which might be recoverable with special tools. Special tools can remove user data by a single overwrite of all files and free space.