Wordpress is a Content Management System focused initially on blogs. However, that system grew in popularity so it was be used not only for posting on blogs but as a editor of content in websites.
That allows to the users and websites owners to take the control of content on a easy way. If your website is designed in this CMS, you can edit and post your pages, post, news, articles, blogs and interesting information in real time by a friendly back end.
Many of informative websites as newspapers uses this system. If your company wants a website where can show the business and share news and updates without spending a lot in webmaster, this is a good solution.