Today WhatsApp has announced the launch of a new feature: chat filters. These will filter your chat list according to different criteria. There are three of these filters, and they appear above the list of chats for easy one-tap access. Their names are very self-explanatory: All, Unread, Groups. So, obviously, tapping on All will show you all of your chats. If you tap Unread, you'll only see those where you have unread messages (whether you haven't opened a chat since new messages came in or those you have marked as unread), and if you tap on Groups you will only see your group...
Source: https://www.gsmarena.com/whatsapp_launches_chat_filters-news-62467.php
