How to use Categories/ best structure to start a blog

[InternOptions]

Hi there

Hope this doesn't sound as "newbie" as I think it does. I am VERY new to wordpress and spent the weekend customising my blog. I am a little confused about how to structure the content though and was hoping for a few quick tips so I don't make a mistake.

Blog: http://www.internoptions.com/blog

Basically I will be having some of my interns blog about the internships they will be going on or are currently on in Australia or New Zealand.

My current understanding is I set up categories for Film Internship, Marketing Internship, PR Internship etc categories and then have students post their diary/ blog posts and assign them to the appropriate category. Is this correct?

If there is a better way that will be more reader friendly I would appreciate you comments.

Kind regards, Jon