Although Mountain Lion has been on our Macs for a few months now, those from Cupertino do not forget that many people still have Lion, and therefore continue to update the operating system released in 2011 so that you are up to date especially in security.
The 10.7.5 update includes interesting news such as inclusion of GateKeeper, Hundreds of new security measures to prevent external attacks and fix errors with Launchpad when we tried to rearrange the icons.
To update you have to go to the Apple Menu and then run System Update. Restart is required with this update.