In addition to voting, Reactions allow you to express your thanks and let your Team know that you need help. They're easy, fun, and give your community a new way to engage with each other on Stack Overflow. Reactions can be added to questions and answers in your Team.
The available reactions are:
To add a reaction, click the smiley face icon under the star icon to see the reactions, and click on the ones you want to use.
As reactions are added by users, a count of the reactions will appear below the smiley face icon.
Clicking on that reaction count will pop up a modal showing you a list of users that reacted to your post.