SOAP stands for Subjective, Objective, Assessment and Plan. It is a standard format for documenting a patient encounter and can be used both for face-to-face encounters as well as triage phone calls.
Subjective = what the patient reports as the problem, symptoms, location, duration, severity, etc.
Objective = the visual and physical examination of the patient (does not apply to phone triage)
Assessment = the diagnosis, or possible diagnosis of the problem
Plan = what the next step in treating the problem will be (medication, tests, referral, follow-up) or in the case of phone triage (work-in appointment vs. home instructions vs. ER)