The system tray is a small area on your computer screen where you can see and access certain icons or notifications related to the programs running in the background.
At the bottom of the screen you'll find the familiar Android system tray. (laptopmag.com)
It is a very lightweight application which lands on system tray easily and warns you about each malicious websites before you visit them. (thewindowsclub.com)
It's no longer mixed in with the other system tray icons. (howtogeek.com)