This is an example page. It differs from a blog article 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. A presentation like this might appear:
Ciao! I'm a cyclist delivery boy by day, aspiring actor at night and this is my website. I live in Los Angeles, I have a big dog named Jack and I like piña coladas. (And catch the rain)
…or something similar:
The XYZ Aggeggi Company was founded in 1971 and has been supplying the public with excellent quality gadgets ever since. Located in Fantasyland, XYZ employs over 2.000 people and makes all sorts of cool gadgets for the Fantasyland community.
As a new WordPress user, you should go to yours Noticeboard to delete this page, and create new ones for your content. Have fun!