Unlike the other programming languages catalogued here, assembly language is not a single language, but rather a group of languages. Each processor family (and sometimes individual processors within a processor family) has its own assembly language.
In contrast to high level languages, data structures and program structures in assembly language are created by directly implementing them on the underlying hardware. So, instead of catalogueing the data structures and program structures that can be built (in assembly language you can build any structures you so desire, including new structures nobody else has ever created), we will compare and contrast the hardware capabilities of various processor families.
If you aren’t fairly familiar with how computers work, you should probably first read basics of computer hardware or this page won’t make any sense at all.
history: The oldest non-machine language, allowing for a more human readable method of writing programs than writing in binary bit patterns (or even hexadecimal patterns).
Assembly languages are close to a one to one correspondence between symbolic instructions and executable machine codes. Assembly languages also include directives to the assembler, directives to the linker, directives for organizing data space, and macros. Macros can be used to combine several assembly language instructions into a high level language-like construct (as well as other purposes). There are cases where a symbolic instruction is translated into more than one machine instruction. But in general, symbolic assembly language instructions correspond to individual executable machine instructions.
Links: http://www.osdata.com/topic/language/asm/asmintro.htm
