AArch64 is a 64-bit instruction set architecture used in computer processors. It is part of the ARM architecture family, designed to improve performance and efficiency for modern computing needs. AArch64 supports a larger address space and enhanced processing capabilities, making it suitable for a wide range of devices, from smartphones to servers. This architecture allows for better multitasking and improved energy efficiency, which is crucial for mobile devices. Many popular operating systems, including Linux and Android, support AArch64, enabling developers to create applications that can take full advantage of its features.