Assembly Source Code File
The low level programming language used for programming computers and other devices is know as assembly language. This uses machine code and other resources that are needed to program the CPU architecture such as instructions, process registers etc and for each CPU architecture a separate assembly language needs to be programmed.
An assembler is used to change the assembly language in to machine code which the computer can understand, many assemblers make it possible to debug as well as control the assembly process and use macros to speed up development.
The source code files written in assembly language make use of the .asm file extension.