Toast notifications are short messages that pop up on your screen to give you important information or alerts. They are called "toast" because they are similar to a toast popping up from a toaster – quick and easily noticeable. Full definition
One nice thing about notifications is that you have the ability to receive toast notifications when severe weather alerts are issued for your forecast city or cities (you get that choice). (windowscentral.com)
For example, breaking news applications sends toast notifications (banners) along with sound whenever there is a breaking news. (thewindowsclub.com)
It does not alert you of missed calls, new emails, new toast notifications, etc.. (windowscentral.com)