Selenium IDE is a Firefox plugin which records and plays back user interactions with the browser. Use this to either create simple scripts or assist in exploratory testing. It can also export Remote Control or WebDriver scripts, though they tend to be somewhat brittle and should be overhauled into some sort of Page Object-y structure for any kind of resiliency.

Features:

1. Allows you to easily and quickly record and play back tests in the actual environment that they will run.

2. You can choose to use its recording capability, or you may edit your scripts by hand.

3. Autocomplete support.

4. Able to move commands around quickly.