A single board computer (SBC) is a type of computer with all of its components built onto a single circuit board. The size of an SBC can vary from about the size of a credit card to that of a video game console. They are often incorporated into larger devices such as automatic teller machines, industrial and medical equipment, or robotic devices. Since the mid 2000s, inexpensive single board computers have been used by educators and hobbyists.
Desktop and even laptop personal computers (PCs) generally have separate components connected to a central circuit board through cables or buses. A single board computer packs all of its necessary components, including the microprocessor, memory, and storage, onto a single circuit board. Many SBCs are built to be PC-compatible and use the same processors, memory, and graphics chips as standard PCs. Other units include different types of hardware and some feature a microcontroller, a specialized processor with built-in input/output functions. Some SBCs are expandable or partially reconfigurable, while others are stuck with what they shipped with.
The size of a single board computer can vary widely, but most are far smaller than a typical PC. The earliest such devices, introduced in the late 1970s and early 1980s, were usually found in educational or development computers, and were quite large. Since then, the trend has been towards smaller SBCs, ranging from a little less than the size of a credit card to about the size of Blu-Ray® player. They can come in both standard and nonstandard sizes, and a few are even built to be the same size as a normal PC expansion card or memory module.
Single board computers are commonly housed inside a larger device or product, thereby providing additional intelligence or controlling the functions of machinery or equipment. Automatic teller machines, cash registers, touch screen kiosks, and many other machines and devices often house an embedded single board computer. They are also used in industrial computers and automation equipment, robotics, medical devices, and many other fields. Due to the number of possible uses, SBCs come in a variety of configurations, and many manufacturers build machines tailored to a specific need or industry application.
By the mid 2000s, the cost of computer components had dropped enough to bring the single board computer within reach of the hobbyist community. Several companies now specialize in low-cost yet versatile SBCs for use in amateur electronics and computing projects. These devices may be used on their own to introduce students to computer programming or as part of a larger platform like a robot or interactive art display.