Programming Evolution

Assembly Language

• A big step up from machine code, it revolutionized programming
• Uses a translator (assembler) to change a symbolic representation of an instruction to machine code
• The assembly instructions are called mnemonics (e.g. ADD, MUL, DIV, JMP) and are used in place of the binary-coded instructions
• The machine code (in our example) for adding the contents of register A (10011011) to a memory location B (11000110) can now be coded as ADD B instead of 1001101111000110
• Much easier to understand which means easier to fix errors that are certain to crop up
• Still processor-dependent because the mnemonics represent the instruction set of a (particular) processor
• Although much easier to understand than machine code, it would be nice to move away from the low-level languages; machine independence would be nice, too

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