Microsoft introduced a nifty way to view all of your notifications at once in the Action Center, which is one of Windows 10's best features compared to Windows 7 or 8.1.
However, it does tend to get clogged up with notifications, including ones that are seemingly useless (we're looking at you, Windows tips). Luckily, turning these off is easy.
Go to Settings > System > Notifications & Actions, and then simply toggle off any that are not useful or relevant while keeping the ones that are. Individual third-party app notifications can also be switched off.