Templates are a subset of your Web Forms. These are the ones you want your users to start from because they have been built and tested to look good and work well.
They are simply the web forms that you have marked as 'Display in Templates' but are still ordinary web forms.
To use a template
You can click the 'Use this template' button under the one you want to use and it will create a clone for you to rename and continue working in. This leaves the original template undisturbed.
To inspect a template first
Click the image or the blue title and you will go straight into that template. Here you can have a good look around to check the form will do what you want before selecting it. You may be able to edit the template while you are inspecting it, depending on its status and your permissions - so tread lightly!
Templates are available in grid view only, sorted A-Z (across, then down).