A test plan can be visualized as your JMeter script for running tests. A test plan consists of test elements such as thread groups, logic controllers, sample-generating controllers, listeners, timers, assertions, and configuration elements.
A test plan consists of all steps which execute the script. Everything which is included in a test plan is executed in a sequence which is top to bottom or as per the defined sequence in the test plan. The figure given below shows the directory level of a test plan.
Important points regarding a Test Plan -