
36 ◾ Software Essentials
2.3 PROGRAMMING LANGUAGE EVOLUTION
Programming languages and soware tools elevate the low-level tedium of
bit evaluation to a conceptual level. Assembly language is the rst layer of
abstraction, replacing command bit strings with pseudo-mnemonic code
that directs the use of registers and memory locations. us, program-
mers work with coded locations rather than direct memory addresses.
Instruction sets for an assembly language are tied to a specic processor
family, yielding little or no portability.
Although an improvement over hard coding binary strings, assembly
languages provided only limited portability due ...