This is an example page. It differs from posts because it always stays in the same place and (for most themes) is displayed in the website navigation. Most start with an imprint, privacy statement, or "about us" page to introduce yourself to potential visitors to the site. For example, it could say:
Hello! during the day I work as a bicycle courier, at night I am an aspiring actor and this is my website. I live in Berlin, have a big dog named Jack, like piña coladas, but less (without umbrella) being left out in the rain.
...or something like this:
The XYZ company was founded in 1971 and has been supplying the public with high quality products ever since. Located in a small city, the company employs over 2,000 people and supports the city's inhabitants in many ways.
As a new WordPress user you should your dashboard to delete this page and create new pages and posts for your website. Have fun!