What is assembly language. Give its advantages over machine language?

Machine language is binary:
0010001111010111011011
1011. Humans can read this
code, but it is tedious and
painfully slow for most
humans to do so.

Assembly language is a
mnemonic language: it
translates directly into
machine code, but is easier
on the eyes. The above
machine language might
translate into a more
readable:

mov r1,3412
mov r2,2231
add r2,r1
push r2

"mov r1,3412" is far easier to
read than a string of 1s and
0s that the computer sees. Of
course, like any language, you
still have to understand the
code, and there is a lot more
documentation to work with
assembly as opposed to high
level languages.

The advantage is that
assembly is easier to read
and write for humans than
pure machine code.