In Blogger, a page is similar to — but not the same as — a post. Both can contain text, pictures, or video. However, pages are meant to hold static content that seldom changes — contact information, “About”, et cetera. Posts are more like diary entries. The following chart shows how they stack up:
As the chart shows, some elements -- like the title -- are included in both pages and posts. But only posts display the date and author. Posts allow "tags", but don't show up in the navigation, which is the row of labels at the top or side of the site containing static resources (like "About", "Home", or other pages created by the author).
In Blogger's Pages section, you can also create a "Page" that is simply a link to another site, like a Twitter or Facebook page. These links appear in the navigation.