Apple released yesterday its first “rapid” security patches for iOS, iPadOS, and macOS, which bring security fixes to the three platforms without the need for incremental system updates. This a new type of software update that Apple announced at its WWDC conference last year, and you’ll need to be running the latest versions of iOS, iPadOS, and macOS to receive them.

“Rapid Security Responses are a new type of software release for iPhone, iPad, and Mac. They deliver important security improvements between software updates — for example, improvements to the Safari web browser, the WebKit framework stack, or other critical system libraries. They may also be used to mitigate some security issues more quickly, such as issues that might have been exploited or reported to exist “in the wild,” Apple explained yesterday.

By default, these “rapid” security updates will be installed automatically, though you can still check for updates manually by going to Settings > General > Software Update. There, you can also choose not to apply these Rapid Security Responses updates when they’re available. However, the new bits will still be included in the next regular software updates for iOS, iPadOS, and macOS.

Notably, installing these “rapid” security updates will add a letter after the version number of the OS. As an example, I’m running iOS 16.4.1 (a) and macOS 13.3.1 (a) after installing these security updates. These two updates were around 80MB so the download was pretty quick, though be aware that a reboot is still required.