What is Gstart & Garmin Express Tray? and how do they relate to Express.

I have Gstart and Express tray auto start when I boot the computer.

I don't see any any sign of the Express tray on the task bar. But Gstart is in Hidden Icon's on the taskbar.

If I plug in a device without Express running I will get a message identifying the Garmin device as a drive and saying that there is a problem with the drive and to scan it. I assume that this is a Windows message.

Then I will get a Garmin pop-up that indicates the device has synced.

If all of this happens without Express running, what is Express for