A. Mechanical - मैकेनिकल
B. Electrical - इलेक्ट्रिकल
C. Electro Magnetic - इलेक्ट्रो मैग्नेटिक
D. Laser technology - लेज़र तकनीक
The optical disc makes use of laser technology: digital data are recorded by burning a series of microscopic holes, or pits, with a laser beam into thin metallic film on the surface.
Laser stands for "Light Amplification by Stimulated Emission of Radiation." In the context of optical disks, a laser is used to read and write data.