8-bit describes a computer architecture that processes data in 8-bit chunks, or one byte at a time. Early home computers such as the ZX Spectrum used 8-bit processors, which meant limited memory, smaller address spaces, and simpler graphics and input systems compared with later 16-bit and 32-bit machines.
In cyber security, 8-bit systems matter because their constraints shape both attack surface and defense. Limited RAM and CPU time can make security features hard to add, while small code bases and simple hardware can also reduce complexity. Many embedded devices and legacy systems still rely on 8-bit designs, so defenders may need to account for weak authentication, fragile input handling, or insecure update paths. Attackers often target these old platforms by exploiting basic software bugs, weak passwords, or unprotected firmware.