Posts are the entries that display in reverse chronological order on your home page. In contrast to pages, posts usually have comments fields beneath them and are included in your site’s RSS feed.
To write a post:
In WordPress, you can write either posts or pages. When you’re writing a regular blog entry, you write a post. Posts automatically appear in reverse chronological order on your blog’s home page. Pages, on the other hand, are for content such as “About Me,” “Contact Me,” etc. Pages live outside of the normal blog chronology, and are often used to present information about yourself or your site that is somehow timeless — information that is always applicable. You can use Pages to organize and manage any amount of content.
Other examples of common pages include Copyright, Legal Information, Reprint Permissions, Company Information, and Accessibility Statement. (By the way, it’s a good idea to always have an about page and a contact page — see this advice from Lorelle.)
In general, Pages are very similar to Posts in that they both have Titles and Content and can use your site’s Presentation Templates to maintain a consistent look throughout your site. Pages, though, have several key distinctions that make them quite different from Posts.