Enter the name of your site (or blog) here. Most themes will display this title, at the top of every page, and in the reader’s browser titlebar(Figure 1).
In a few words, explain what your site is about. Your sites’ slogan, or tagline, might be entered here. A tagline is a short phrase, or sentence, used to convey the essence of the site and is often funny or eye-catching.
Adding Site Title and Tagline
To add a Site title and Tagline for your website, go to Dashboard > Settings > General, enter the title and tagline in the respective fields(Figure 2).
More Information: https://codex.wordpress.org/Settings_General_Screen