The site editor enables you to change the colour, fonts and background of your page and add some other features like contacts, maps and comments.
The basic idea is to post a photo (drag-and-drop it straight to the page) and add some information about it. The customization of the page is elementary, that is why it is perfectly suitable for inexperienced web users.
I see this tool as a fantastic possibility for students to create short term projects and share them online. It can be a study project, a description of a trip or school event, a drawing made by the student or even a presentation. The best thing is you don't have to register to create your webpage but in that case your page will expire in one month. If you want to keep it longer, you have to register.
Here is the page I made to see how the tool works http://tackk.com/jl018w