Growl Growl is a notification system for OS X. Growl has been around since 2004, and was originally called Global Notifications Center. The name was changed to Growl (like the noise a dog makes) since we felt the name Notifications Center was too geeky. We were wrong about that haha. Growl was meant as a proof of concept which became something more for a long period of time. Before Growl was made