Direct-to-disk recording (DDR) refers to methods by which analog signals and digital signals such as digital audio and digital video are digitally recorded to optical disc recording technologies such as DVDs, and CD optical discs. Magnetic storage includes hard drives (HDD), magnetic tape such as videotape and is different from flash memory.
Generally these devices have the ability to convert analog signals into computer files.
Direct to disk can involve permanent or semi-permanent non-volatile memory recording media. Computer hard disk drives are random access, erasable and rewritable non-volatile recording devices but have been referred to as "permanent" by some manufacturers of direct to disk systems.
In 1982, New England Digital offered an optional hard disk recorder package for their Synclavier which allowed digital recording of monophonic 16-bit 50 kHz audio direct to a hard drive; this was the first digital direct to disk audio recorder available commercially. Stereo audio was not immediately available due to data input and output limitations on hard drives of that time.
Today, a majority of digital audio recording is preserved on hard disk drives.