A new feature in Google Mail - Tabbed Inbox
There is a new feature in the Google Mail that you may enable. If enabled, Google will now read your emails and classify them into tabs, such as Primary, Social, or Promotions. There are also other tabs that you can enable should you choose to do so. This is refereed to as "tabbed email." Much like browser tabs, you can now have email tabs with each tab classifying and organizing your emails. If you choose to enable this feature, your inbox will look something like the picture below.
You can see that I have a Primary Tab, a Social Tab (for things like Facebook, Twitter, etc), and Promotions tab (these would items coming from my resellers, such as Amazon). You can also choose to have other tabs show on your inbox.
What if emails land inside the wrong tab? No problem, just drag the email to the tab with which you want it associated.
To enable this feature, simply click the settings button (the wheel or clog) on the right side of your email pane, then drag down to "Configure Inbox". You then choose the tabs you would like to enable and press "Save." Once complete, your inbox will look similar to the picture above.
For more information about tabbed email, please visit the google help page at https://support.google.com/mail/answer/3055016?hl=en