A SWOT analysis is one of the techniques that PMI recommends as part of the identify risks process (section 184.108.40.206 in the PMBOK 5th edition). SWOT stands for the 4 different types of risk to consider: strengths, weaknesses, opportunities, and threats.
This framework helps identify risks. And by classifying the type of risk, it also informs the types of responses in the later process to plan risk responses. For instance, a project might mitigate an internal weakness by training. While other techniques are probably more appropriate for exploiting an internal strength.