At first glance, pages look very similar to posts. Both pages and posts have a title and a content area in which we can write extended text, add images, and so on. However, pages are handled quite differently from posts. First of all, pages don't have categories or tags (pages don't need to be categorized, since on most websites, there are a lot fewer pages than posts). Moreover, posts belong to your blog and are meant to be a part of an ongoing, expanding publication revolving around specific topics. Posts are added regularly, whereas pages are more static and aren't generally expected to change that much.
In short, I would advise you to think of pages as pieces of static content, and posts as a series of articles that are published in a timely manner. In other words, pages are meant to hold content that is equally up to date, no matter when someone reads...