Many Disc-Based Enclosed Media (DBEM) formats look similar on the exterior, but use different underlying recording technologies. There are three main kinds of recording methods for optical disks; ablative (WORM), magneto-optical, and phase-change.

This is a strictly Write-Once, Read-Many (WORM) format that relies on physical ablation. When data is written, a high-powered laser beam physically melts, burns, or vaporizes microscopic pits or bubbles into the active recording layer of the disk. Because this causes a permanent physical deformation of the material surface, the data cannot be erased or overwritten, achieving a permanent, tamper-proof archival record¹⁾. This recording method can be used for secure data erasure as all traces of the original data can be destroyed instead of overwritten or obscured.