This is a sample page. It's different from a blog post because it stays fixed in a specific place and its title is displayed in your theme's navigation menu (most themes support it). Many people use an About page to welcome potential visitors. A page that looks something like this:

Hello there! I'm a bike messenger by day and an aspiring actor by night, and this is my website. I live in Istanbul, I have a wonderful dog named Bıdık and I love drinking piña coladas (and getting caught in the rain.)

...or something like that:

XYZ was founded in 1971 and has been making quality things ever since. Based in Gotham City, XYZ employs over 2,000 people and strives to do the best for Gotham City.

As a new WordPress user, you should first go to the start page, delete this page and create your own pages. Have fun!