Go to mange site by press g and then m
To change the name of site which is appearing on the tab you have change in the Site name text box. So what is in that text box will appear in the top.
This will help to during SEO of website. When you give in detail about your website then search engines can easily know about your website and can index them.
Please see whether you website is having any content for adults if yes please check the box. If it is not there kindly don’t check. If it is personal website then you should not have them. It will reduce your viewers .
user who can visit the site for this setting make it to Anyone who can view this site and
User who can access revision history for this setting make it to collaborators only