You do not need an account on CleverTrail to view trails or even to make edits. However, there are many benefits to creating an account:
You can then go to your account page and see a trail map that shows all the trails you have marked as complete. This is a fun way to track your trails and remind yourself where you've been. Your account page can be found by clicking on your user name in the upper left (in the grey toolbar) and then on the "my page" link.
Marking trails as "done" is how you promote your Hiking Title (see below).
You might notice that when you first register with CleverTrail, you will have a grey colored hiking badge next to your name in the toolbar (in the upper right corner). This is your Hiking Title (mousing over it will give the title text). Your Hiking Title gets promoted when you mark trails as "done" (see the section above) and corresponds to the following ranges:
You can also see your Hiking Title on your User Page (click your User Name on the toolbar and then "my page") as well as any other user's Hiking Title on his or her User Page. Additionally, when you post comments on a trail, your Hiking Title will show up next to your name.