During the installation you get to choose your sites’ title. WordPress automatically adds a tagline to your site title that says Just Another WordPress Site.

You can change the title and tagline by following Settings-General page.

Your site title will be the name of your website like WP Dean. The tagline is usually a single line describing your website. You can also leave the tagline blank if you wish.

Dont forget to click on save changes button to store your settings.