This is a sample page. It differs from a post because it has a fixed location and is shown in the site navigation (in most themes). Most users start with an About Me page to introduce themselves to potential visitors. For example:
Hello. By day I'm a mailman, but by night I'm carpentry as an actor. This is my blog. I live in Hilversum, together with Vlekkie, my faithful four-legged friend. I love cocktails and, occasionally, a summer shower on my head.
...or something like that:
XYZ Dingetjes BV has been supplying countless dingsetjes of high quality to a wide audience since 1971. Based in Bolsward, XYZ has about 2,000 employees and does all kinds of great things for the Frisian community.
As a new WordPress user, you can go to the dashboard to delete this sample page and create new pages for your site. Have fun.