This is an example page. It differs from a blog post because it stays in the same place and (in many themes) appears in the navigation menu. Many people start with an About page that introduces them to site visitors. It might look something like this:
Hi! I'm a bike messenger by day, aspiring actor by night, and this is my website. I live in Los Angeles, have a big dog named Jack, and enjoy piña coladas. (And catching rain.)
…or something like that:
XYZ Gadgets was founded in 1971 and has been providing the public with high-quality gadgets ever since. Located in Fantasilandia, XYZ employs over 2,000 people and manufactures all kinds of fantastic gadgets for the Fantasilandia community.
As a new WordPress user, you should go to your Dashboard to delete this page and create new ones for your content. Have fun!