SBCs (Single Board Computers) are small (generally having a credit card sized footprint) usually inexpensive ($20-$100 though there are now many well above this amount) computers that can do most general computing tasks (popular uses are webserver, voip interface, network router/bridge, htpc, console emulator, etc., but they can of course also be used for web-browsing, the standard office suite [text editing, spreadsheets, databases, presentation slides, graphics editing, etc.], modeling software, programming IDEs, etc.)

• Raspberry Pi