Backup of a project (.MFA) file created with Multimedia Fusion, a game development program; generated by the program's Autobackup feature; allows the project to be restored in case the original file becomes corrupted or is accidentally deleted.

NOTE: Multimedia Fusion may create multiple backup files with the extensions ".001," ".002," etc, depending on how many backup copies have been selected in the program preferences.

Backup of a hard disk created with Norton Ghost; created when a backup is split into multiple files due to the 2GB file size limit in DOS; other parts of the split backup have extensions ".002," ".003," etc.

Split backups created with Norton Ghost also include a .GHO file, which contains information about the backup files and is necessary for restoring the backup. NOTE: Norton Ghost was renamed as Ghost Solution Suite.

Saved game state created by Snes9x, a Super Nintendo Entertainment System (SNES) emulator; contains a game snapshot saved in the second of nine slots (slots 1-9); used to save and load SNES emulated game states.

Saved game slots 1-9 correspond to file extensions ".000" through ".009" on the Windows version of Snes9x. Their files are named using the ROM name followed by the respective slot extension. For example, GameA slot 2 would be named GameA.001. Saved states are stored in the Saves directory of an Snes9x installation. On Mac versions of Snes9x, saved states use the the extension .FRZ ("frozen" states). NOTE: Unlike a normal game saved state, which may only be created at certain points in the game, 001 files can be created at any time during gameplay.

A 001 file is the first file of a split archive created with various file splitting and joining utilities. It is used to split large archives into smaller, more manageable files. 001 files can be used for saving files onto multiple storage devices, such as USB drives or CDs, or for creating smaller email attachments.

An 001 file is one part of a larger archive, which means there is at least one more split archive associated with the file. Each part of a split archive is given an ascending number extension, which are .002, .003, etc. NOTE: Programs such as 7-Zip use compound extensions for split archives. For example, 7-Zip creates split archives with the .7Z.001, .7Z.002, etc. extensions.