Multiple Biog sections in a single WP site?

It is not clear what you means. But you can separate your posts to different section using several ways. The main ways are
1. Taxonomis.
2. Cusom post types.
Taxonomies helps you to categorize your posts.
Custom Post types helps you to create another division. You can use Types plugin for this.

I also want to have one WP site with more than one blog section and will follow the answers with great interest.

Often times, it is enough to have all of your blog posts in one place (i.e. Posts) and then simply filter out the correct posts as you need them based on tagging and categories. The tags or categories can be the different topics. For most situations, this should be enough functionality.

If you want to split the content into multiple sections, be sure that you have a good underlying reason, as it will require more long-term maintenance to support.

Thank you Hannah, but tagging and categories is not what I am looking for.
One example could be to have a site for my travels. I would like to have two “sections” about
Paris 2015, London 2016 with blog posts in each. Let us call them London and Paris to simplify.
When I am in London, I would like my blog entries to end up in “London”. And when I go to Paris, I would like my entries to end up in Paris. i would like to control where I post my blog entries.
Maybe this is old fashioned, but this is how I would like to do.
And I assume this is how sean.miller also would like to do. Am I right sean.miller?

Think of categories as “sections”. All you need to do is set up top-level categories for (suing your example) ‘Paris 2016″, ‘Londan 2015″, etc. Then choose the category. That way you can also have sub-categories, like “Paris 2016 -> Eifel Tower” and those poss will appear under the main “Paris 2016” category as well. There’s no reason to make things more complicated than that.