Define addressing mode and pipelining

Addressing mode: the method by which an instruction specifies the location of its operand. It tells the processor how to compute the effective address of the data. Common modes: immediate (operand in the instruction), register, direct (address given), register indirect (register holds the address), indexed/base-plus-offset and relative. Example: MOV A, #25H (immediate); MOV A, 30H (direct); MOV A, @R0 (register indirect).

Pipelining: a technique that overlaps the execution of multiple instructions by dividing instruction processing into stages (fetch, decode, execute, memory, write-back), each working on a different instruction in the same clock cycle. It increases instruction throughput (ideally one instruction per cycle) without shortening the time for each individual instruction.