Mini CMS

Hi,

I’m wanting to build a mini CMS in RoR and have got to grips with the
terminology, can link up to databases etc.
I have 3 pages, Home, About and Portfolio and want these to have an
admin area where I can let people add and delete content. What would be
the best way to log people in using sessions?

I was thinking that with a page like portfolio which would hold images,
text etc., the editing page would be at “app/portfolio/edit.html.erb”.
How could I stop a internet user from seeing this page and only allow
them to see “app/portfolio/index.html.erb”?

Thanks for any advice.
Clinton