What does a assembly language code look like?

Machine language is all binary numbers, and will vary on different architectures. For example, on a 32 bit processor, instructions will come in the form of a sequence of 32 "1"s or "0"s, where maybe the first 5 tell the CPU which instruction is being performed (add, subtract, load memory into register, load register into memory, etc), if you are adding maybe the next 5 bits means register $eax, the next 5 bits could be register $ebx.

The actual instruction will look something like: 01101001011010001100110011001100