direct attached storage - technical definition

Disk drives contained within the computer cabinet and connected to the CPU via PCI or some other peripheral bus. Most users' computers and most servers have direct attached storage (DAS). Contrast with "storage area network" (SAN), which extends direct attached storage to external disk arrays shared by many servers. Also contrast with "network attached storage" (NAS), which adds file storage on the network. See block level, SAN, NAS and RAID.