FreeOTFE is an encryption computer program aimed at both Windows desktop and mobile users. Developed by independent developer, Sarah Dean, the program fully functions as a virtual disk creator that is fully encrypted prior to storage procedures. Encryption is the process of protecting any data before storing it to any available storage in a computer's processing memory. This was developed in 2004 as an open-source code disk on-the-fly encryption program.
It was the first of its kind to be available for third party interference focused on implementing additional algorithms according to how the program is used. FreeOTFE is also compatible with Unix systems and can also be portable. It is open-source but requires attribution. This is the first open source program to fully support both Windows and PDAs.
Due to its portability feature, the program itself can be saved in a flash drive, portable hard disk, or CD. This makes the FreeOTFE available for use even without actual installation. Users can easily mount it to any device that accepts flash disks and the whole encryption can start. Without installation, the program requires users to temporarily install device drivers to make way for the storage of finished encrypted files. This process requires administrative privileges.