Segment Registers

• CS [code segment] - the block of memory where the code (instructions are located)
• DS [data segment] - the block of memory where data can be accessed. In block move operations in which huge blocks of memory are moved this is commonly the segment in which the CPU reads from.
• ES [extra segment] - also another data segment. In block move operations in which huge blocks of memory are moved, this is commonly the segment in which the CPU writes to.
• SS [stack segment] - this is the block of memory in which the CPU uses to store return addresses from subroutines.