Block storage refers to the direct access to random disk blocks in computer disk storage. Block storage is normally abstracted by a file system for use by programs and end users. This term is generally used for internal disks. This low-level access method is also used by storage area networks (SAN) and iSCSI protocol. Block I/O is typically used to bypass caching in the operating system layer such as a file system and gain performance. High performance applications such as database systems typically use Block I/O. In computer science, random access is the ability to access a random element of a group in equal time. ... Disk storage is a group of data storage mechanisms for computers; data are transferred to planar surfaces or disks for temporary or permanent storage. ... In computing, a file system is a method for storing and organizing computer files and the data they contain to make it easy to find and access them. ... In computing, a storage area network (SAN) is a network designed to attach computer storage devices such as disk array controllers and tape libraries to servers. ... In the context of computer storage, Internet SCSI (iSCSI) is an official standard ratified on February 11, 2003 by the Internet Engineering Task Force, uses the SCSI protocol over a TCP/IP network. ...