which perform indicated operations on two fast registers of the machine and have the result in one of the registers
which perform an operation on a register operand and an operand which is located in the main store, generally leaving the result in the register, expect in the case of store operation when it is also
to recognize the major constructs of the language and to call the appropriate action routines that will generate the intermediate form or matrix for these constructs.
to parse the source program into the basic elements or tokens of the language.