User Testing is a way for researchers to test the functionality of a website, app, or other digital product.
You would first define the testing objectives to outline what it is you want to test and what information you expect to obtain. Then choose a user testing method depending on what stage of the development cycle you are in. Find representative users who match your needed user profile and selected criteria. Create task scenarios, such as asking the user to get from the home page to the contact us page and reviewing how many steps it took the user to get there. Replicate the testing envirnment, this will ensure that the results will be accurate, by providing a script for the users this will ensure it is able to be replicated and consistent. Finally analyse your findings, use these results to identify possible issues, prioritize them and determine the best course of action to improve.
Different versions of browsers are tested by testing your page on different browsers and ensuring the page works consistently and as intended, you also will do this with a few past versions and even the future version of browsers such as Safari and Chrome.