Joomla is a CMS with blogging capabilities and Wordpress is blogging sofware with some content management.

We use both depending, so this is our own independent view of Joomla and Wordpress as each has strengths. 

Wordpress makes blogging easy. For simply adding articles it is unsurpassed. It's weakness is in flexibility. It is tricky to manage large amounts of content selectively showing over various pages without having coding knowledge.

Joomla is an award-winning CMS (content management system). It's ease-of-use and extensibility, have made Joomla the most popular website software available. 

What's a content management system (CMS)?

A CMS stores and keeps track of every piece of content on your website. Content can be  text, photos, music, video, documents etc. One advantage of using a CMS is that it requires almost no technical skill or knowledge to manage. Since the CMS manages all your content, you don't have to.