Optical disc the DataPlay format, can have capacity comparable to that of the larger, standard compact 12 cm disc. Third-generation optical discs are in development, meant for distributing high-definition video and support greater data storage capacities, accomplished with short-wavelength visible-light lasers and greater numerical apertures. Blu-ray Disc and HD DVD uses blue-violet lasers and focusing optics of greater aperture, for use with discs with smaller pits and lands, thereby greater data storage capacity per layer. In practice, the effective multimedia presentation capacity is improved with enhanced video data compression codecs such as H.264/MPEG-4 AVC and VC-1. The following formats go beyond the
Optical disc drive CD, similar to the tray ejecting method used in internal optical disc drives of modern laptops and modern external slim portable optical disc drives. Like the top-loading mechanism, they have spring-loaded ball bearings on the spindle. Most internal drives for personal computers, servers and workstations are designed to fit in a standard 5.25" drive bay and connect to their host via an ATA or SATA interface. Additionally, there may be digital and analog outputs for audio. The outputs may be connected via a header cable to the sound card or the motherboard. At one time, computer software resembling CD players