As a reminder, this project is being built upon the following starter project on [Repl.it](https://repl.it/github/freeCodeCamp/boilerplate-mochachai), or cloned from [GitHub](https://github.com/freeCodeCamp/boilerplate-mochachai/).
A headless browser is a web browser without a graphical user interface. This kind of tool is particularly useful for testing web pages, as it is able to render and understand HTML, CSS, and JavaScript the same way a browser would.
For these challenges we are using Zombie.JS. It's a lightweight browser which is totally based on JS, without relying on additional binaries to be installed. This feature makes it usable in an environment such as Repl.it. There are many other (more powerful) options.
Mocha allows you to prepare the ground running some code before the actual tests. This can be useful for example to create items in the database, which will be used in the successive tests.
With a headless browser, before the actual testing, we need to **visit** the page we are going to inspect. The `suiteSetup` 'hook' is executed only once at the suite startup. Other different hook types can be executed before each test, after each test, or at the end of a suite. See the Mocha docs for more information.
Within `tests/2_functional-tests.js`, at the root level of the `'Functional Tests with Zombie.js'` suite, instantiate a new instance of the `Browser` object with the following code: