What is Assertion????
Asserts helps us to verify the conditions of the test and decide whether test has failed or passed. A test is considered successful ONLY if it is completed without throwing any exception.
Here we are verifying if the page title is equal to 'Google' or not. If the page title is not matching with the text / title that we provided, it will fail the test case.
To explain you what is assertion, lets us look into below code sample