Addressing modes are methods for the CPU to access operands or data. Various addressing modes include:

• Immediate Addressing: The operand is directly specified in the instruction.
• Direct Addressing: The address field holds the memory location of the operand.
• Indirect Addressing: The address points to a memory location containing the operand’s actual address.
• Indexed Addressing: Combines a base address with an index for locating data.

Each addressing mode offers unique advantages and trade-offs in terms of speed and memory usage. Addressing modes are a crucial part of COA, as they impact the efficiency of data handling within the CPU.