ARM8, or ARMv8, is a 64-bit processor architecture developed by ARM Holdings. It introduced significant improvements over its 32-bit predecessor, ARMv7, including support for larger memory addressing, improved performance, and enhanced security features such as TrustZone. ARMv8 is widely used in smartphones, tablets, servers, and embedded systems, offering efficient power consumption and high processing capability, making it ideal for modern computing and mobile devices.