Chatter supports the ability to insert emojis into your posts. That's right! You can get emojinal!
Posts in private and unlisted Chatter groups have a seen-by count that shows the number of people who have seen a post. Click the count to see the names of people who’ve seen the post.
Resource:
Chatter Group Seen-By Counts Help Article - https://help.salesforce.com/articleView?id=collab_group_s...
In this lesson we look at how to enable the Chatter app by profile. We also cover various System Permissions related to Chatter, which can be set at the Profile or Permission Set level.
Chatter streams are custom feeds that you create by combining multiple related feeds into one feed. Look for Streams on your Chatter home page.
Resource:
Chatter Streams Overview - https://help.salesforce.com/articleView?id=collab_chatter_streams_overview.htm&type=5