WordPress allows you to create Posts AND Pages.
POSTS
Posts are those snippets of information that you write as you are blogging. Posts display one atop another in descending chronological order by date. When you write a Post, a date is automatically assigned. You can change the date, but, the point is that the Post is associated with a date and time, and WordPress uses the date to automatically archive the Post. A Post is associated with a category (that you assign), and could have tags assigned as well. So a visitor can reach the Post by seeing it listed in the blog, seeing it listed by category, tag, or date.
Even though a Post may no longer display on your blog page, it lives forever and ever in your blog (unless you explicitly delete it – which is a bad idea).
PAGES
Pages are for more permanent pieces of information. They are not associated with a date, so they always display on your blog, and, will not be aged (pushed lower down on the blog page or added to the archive) like Posts. They are not associated with categories either.
Pages stand on their own. So the way to access a page is to click on the title of the Page.
Pages are usually listed as a separate section on the blog menu as are Posts, Recent Comments, Recent Posts, Polls, Search, etc.
In WordPress, the way you create a Page and create a Post is almost exactly the same, and the editing interface is as well.
When do you use a Page instead of a Post
Here’s how I decide. When I write information that I want to share in a blogging sort of way, like this for example, I write a Post. When I have information that I want to share and it is mostly static… like a course syllabus… I write that on a Page. It tends to be longer than a typical post and the content of the course will not change. The prerequisites are the prerequisites and the topics to be covered are the topics to be covered. What changes about the course are the dates and locations. So, I blog (write Posts) about those and in the Posts, I link to the Course Syllabus.
Recap: So Course Announcements I write as Posts because the date, times, and locations change, and Course Syllabi I write on Pages because the content doesn’t change.
Other example, I would use a Page to write bio about myself and a Post to announce where I will be presenting. My Post would link to my Bio as above my Post linked to the Course Syllabus.