A Virtual User is the simulation of a real life browser user that performs the Web activity you want during a Test-run. The activity of Virtual Users is controlled by recording and modeling the Scripts that represent the Web activity you want to Test. They are generated when a Script-based Task Group is executed during a Test-run and are used to produce the load levels you need against target WAEs.
A software entity, internal to Web Performance Trainer TM, that simulates a real user by repeatedly performing a Business Case during a load test.
A Virtual User is the simulation of a real life user that performs the activity you specify during a Test-run. You control the activity of your Virtual Users by recording and modeling the Scripts that represent the activity you want. When the Test that includes the Script is run, the Script is replayed exactly as the browser made the original requests.