Condition codes in the context of a computer processor are the extra bits retained by the processor to enable it decode the results obtained from a prior operation, as well as the information needed for the execution of future instructions. These bits are collected and stored together in a single condition or indicator register (CR/IR) or grouped with other status bits into a status register (PSW/PSR).
There are four(4) major functions of the condition codes:
1. They help in the evaluation of boolean expressions
2. They help in conditional control flow, or branching
3. Overflow detection is possible because of condition codes
4. Multi-precision arithmetic is as a result of condition codes.