A single-board computer is a complete computer built on a single circuit board, with microprocessor, memory, input/output and other features required of a functional computer. Single-board computers were made as demonstration or development systems, for educational systems, many types of home computers or portable computers integrate all their functions onto a single printed circuit board. Unlike a desktop computer, single board computers often do not rely on expansion slots for peripheral functions or expansion. Single board computers have been using a wide range of microprocessors. Simple designs, such as built by hobbyists, often use static RAM. Other types, such as servers, would perform similar to a server computer. A computer-on-module is a type of single-board computer made to plug into a board, baseboard. The first true single-board computer called the dyna-micro was based on the Intel C8080A, and also used Intels first EPROM, the C1702A. The dyna-micro was re-branded by E&L Instruments of Derby, CT in 1976 as the MMD-1 and was famous as the example microcomputer in the very popular 8080 BugBook series of the time. SBCs also figured heavily in the history of home computers, for example in the Acorn Electron. Other typical early single board computers like the KIM-1 were often shipped without enclosure, which had to be added by the owner, other examples are the Ferguson Big Board, as the PC market became more prevalent, fewer SBCs were being used in computers. The main components were assembled on a motherboard, and peripheral components such as ports, disk drive controllers. Plug-in cards are now more commonly high performance graphics cards, high end RAID controllers, Single board computers were made possible by increasing density of integrated circuits. A single-board configuration reduces a systems overall cost, by reducing the number of circuit boards required, by putting all the functions on one board, a smaller overall system can be obtained, for example, as in notebook computers. Connectors are a frequent source of reliability problems, so a single-board system eliminates these problems, Single board computers are now commonly defined across two distinct architectures, no slots and slot support. Embedded SBCs are units providing all the required I/O with no provision for plug-in cards, applications are typically gaming, kiosk, and machine control automation. The term Single Board Computer now generally applies to an architecture where the board computer is plugged into a backplane to provide for I/O cards. In the case of PC104, the bus is not a backplane in the traditional sense but is a series of pin connectors allowing I/O boards to be stacked
Image: Raspberry Pi 2 Bare BR
A socket 3 based 486 SBC with power supply and flatscreen
Close up of SBC
ClearFog SBC by SolidRun, based on a Arm Cortex-A9 Dual SoC.