TestPlan –It is a thread group used to hold vaarious thread groups (test cases)
Thread group-Thread group is used to add threads or users to jmeter. Thread group is like a test case in testing. We can create a new thread group and give it any name we want.
Threads-These are basically users by which we want to put load on a website.
Sampler-Like a test step used to send a request to the server.
Listener-Different type of listeners used to generate various types of reports.
Assertions-Used to validate something
Timers-Used to put delay in our application
Controller-Used to provide various logics like if this test condtion is true run this thread group etc.
Config element-If we want to provide some data to the server which we want to read from a csv file or a note pad file we use Config element.
Pre-processor-Going to execute before the sampler. Used to provide data to the server.
Post processor- used to fetch data from server. It is used to to just fetch the data and assertions are used to validate that data or compare it with something.