In a bid to de-clutter and have a more organized Emails, Google started rolling out the new Interface. This works just as the labels work. However, it is much easier to move through from one tab to another and the emails are much better filtered. The default tabs include;
Primary
This contains Messages from friends and family, as well as any other messages that don’t appear in other tabs (including SPAM which may have passed their enhanced filter).
Promotions
This contains your deals, offers, and other promotional emails.
Social
Now, this is a great innovation. Most of us were already getting nagged my finding our inboxes with notifications from our Facebook (mostly) and twitter. Well, this tab has now got your back covered. Messages from social networks, media-sharing sites, online dating services, gaming platforms, and other social websites are found here.
Updates
This tab contains Notifications such as confirmations, receipts, bills, and statements.
Forums
This tab contains Messages from online groups, discussion boards, and mailing lists.
When you receive an email, you see a notification against the respective category showing how many new Mails are unread.
Whether you use tabs or not, all messages are automatically sorted into one of the five different categories.
For more details, watch this video http://youtu.be/RDZL2mxWZtI