This is a sample page. It differs from a blog post because it always 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 like this:
Hi! I’m a bike courier by day, an aspiring actor by night, and this is my website. I live in Los Angeles, have a big dog named Jack, and love piña coladas. (And getting caught in the rain)
…or something like this:
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 sorts 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!