By Joe Hutsko, Barbara Boyd

When your Mac wants to tell you or remind you of something, it alerts you. It used to be those alerts were few and far between, but today with bells ringing for birthdays, beeps telling you you’ve got mail, and banners flying across the screen with the latest tweet, your Mac can sound like a noisy traffic jam.

From Notification Center, you can define how you want to be alerted by any app that might generate an alert. It’s managed in System Preferences, and you view the Notification Center by clicking its button at the far right end of the status bar.

There are several types of notifications, which you can turn on or off for each app that notifies you of something:

  • Banners are mini-windows that appear for a few seconds in the upper-right corner of your screen and then disappear automatically.

  • Alerts are banners that remain onscreen until you click an action button, such as Reply or Later.

  • Badges appear on the app icons on the Dock and Launchpad as white numbers in red circles, indicate the number of items that need attending, which can be messages to be read or apps to update.

  • Sounds play to let you know an app or your Mac needs your attention.

  • Notification Center holds items from various apps, such as a Facebook post by someone you follow or upcoming calendar events.