A scenario is the overall definition of a test. A scenario defines the events that occur during each testing session. It defines and controls the number of users to emulate, the actions that they perform, and the machines on which they run their emulations.
A scenario has one or more scenario groups. A scenario consists of groups of Virtual Users or VUsers, which emulate human users interacting with application executing a test script. Virtual User is the software simulation of a real-world user and a session represents what it does.
Once the scenario is created, LOAD TEST saves the scenario details in a scenario file.
LOAD TEST have scenario profiles to keep default configurations specific to a subproject at a commonplace. This is in replacement for an existing file, which is used as a default configuration file for the controller.