The term 'aarch64' itself is not a standard file extension like '.exe' or '.bin', but rather refers to the 64-bit ARM architecture instruction set (also known as ARMv8-A). When encountered in a file context, it typically signifies that the file is a compiled binary executable or object code specifically compiled for the AArch64 architecture. These files contain machine code instructions directly executable by processors implementing the ARMv8 architecture, commonly found in modern smartphones, tablets, and embedded systems running 64-bit ARM operating systems like Android, iOS, or Linux distributions compiled for ARM. The actual file extension associated with these binaries often varies depending on the operating system and linking format used, such as ELF (Executable and Linkable Format) on Linux/Android, or Mach-O on macOS/iOS. Therefore, 'aarch64' acts more as a descriptor of the binary's target platform rather than a universal file extension.