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_includes/testing.md

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+# Testing
+
+Writing automated tests for your PHP code is considered a best practice and can lead to well-built
+applications. Automated tests are a great tool for making sure your application
+does not break when you are making changes or adding new functionality.
+
+Some common tools are:
+
+* [PHPUnit](http://phpunit.de) is the dominant [unit-testing](http://en.wikipedia.org/wiki/Unit_testing) framework used
+by PHP developers
+* [Behat](http://behat.org) is testing framework for those who prefer to 
+use [Behaviour Driven Development](http://en.wikipedia.org/wiki/Behaviour-driven_development) to
+test their applications
+* [Selenium](http://seleniumhq.org/) is a tool that can automate browser usage
+for testing purposes
+
+[Back to Top](#top){.top}