There's huge amount of browser emulators out there, like Goutte, Selenium, Sahi and others. They all do the same job, but do it very differently. They behave differently and have very different API's. But, what's more important, there is actually 2 completely different types of browser emulators out there:
- Headless browser emulators
- Browser controllers
First type browsers are simple pure HTTP specification implementations, like Goutte. Those browser emulators send a real HTTP requests against an application and parse the response content. They are very simple to run and configure, because this type of emulators can be written in any available programming language and can be run through console on servers without GUI. Headless emulators have both advantages and disadvantages. Advantages are simplicity, speed and ability to run it without the need of a real browser. But this type of browsers has one big disadvantage, they have no JS/AJAX support. So, you can't test your rich GUI web applications with headless browsers.
Second browser emulators type are browser controllers. Those emulators aims to control the real browser. That's right, a program to control another program. Browser controllers simulate user interactions on browser and are able to retrieve actual information from current browser page. Selenium and Sahi are the two most famous browser controllers. The main advantage of browser controllers usage is the support for JS/AJAX interactions on page. Disadvantage is that such browser emulators require the installed browser, extra configuration and are usually much slower than headless counterparts.
So, the easy answer is to choose the best emulator for your project and use its API for testing. But as we've already seen, both browser types have both advantages and disadvantages. If you choose headless browser emulator, you will not be able to test your JS/AJAX pages. And if you choose browser controller, your overall test suite will become very slow at some point. So, in real world we should use both! And that's why you need a Mink.
Mink removes API differences between different browser emulators providing different drivers (read in :doc:`/guides/drivers` chapter) for every browser emulator and providing you with the easy way to control the browser (:doc:`/guides/session`), traverse pages (:doc:`/guides/traversing-pages`) or manipulate page elements (:doc:`/guides/manipulating-pages`).