Organizing 3 Categories of Posts on one Page

So I am building a fairly large site, that will include community-submitted blogs. I have a somewhat complex question:

If I want to have 3 different categories of blogs, and then display these all on the posts page of the site in 3 columns, each column showing posts from one of the categories, how would I go about doing this?

For example, when a user submits a blog post in one of the three categories, it is shown in the posts list for the category it was set in.

I’m guessing you would call the posts 3 different times, each time filtering to a keyword or category?