Signatures can also be used to ensure that one program replacing another is truly an "update", and carry any special security privileges across to the new version.This reduces the number of user security prompts, and the likelihood of the user being trained to simply clicking "OK" to everything.Leopard can run on older hardware as long as they have a G4 upgrade installed running at the 867 MHz or faster, have at least 9 GB free of hard drive space, 512 MB RAM and have a DVD drive.
When first discussed in June 2005, Jobs had stated that Apple intended to release Leopard at the end of 2006 or early 2007.
As always, be sure to back up your Mac with Time Machine before installing any system updates.
The simplest way for most users to gain access to OS X 10.10.1 is through the software update mechanism within the Mac App Store: Mac users can also choose to install the OS X 10.10.1 update through a combo updater, which should be available shortly.
Leopard introduces a significantly revised desktop, with a redesigned Dock, Stacks, a semitransparent menu bar, and an updated Finder that incorporates the Cover Flow visual navigation interface first seen in i Tunes.
Other notable features include support for writing 64-bit graphical user interface applications, an automated backup utility called Time Machine, support for Spotlight searches across multiple machines, and the inclusion of Front Row and Photo Booth, which were previously included with only some Mac models.