What is the red dot on the touch button of Xiaomi mobile phone?

A red dot appeared on the touch button of Xiaomi's mobile phone because it accidentally touched the phone settings. The solution is as follows.

1, open phone settings, and then click Notifications and Status Bar.

2. Then click Notification Management. Click the icon for the application you want to block in little red dot.

3, close the corner of the desktop icon, you can.