TestNG Annotations

What is TesNG and What are the annotations in the TestNG?
     Ans: TestNG is testing framework to run the test cases. TestNG supports annotations like:
      @BeforeSuite
         @BeforeTest
           @BeforeClss
              @Test
              @Dataprovider
              @Cachelookup
           @AfterClass
         @AfterTest
       @AfterSuite