how can i update my mac os x 10.7.5
macOS macOS can be updated using the Mac App Store application[153] or the softwareupdate command line utility. Until OS X 10.8 Mountain Lion, a separate Software Update application performed this functionality. In Mountain Lion and later, this was merged into the Mac App Store application, although the underlying update mechanism remains unchanged and is fundamentally different than the download mechanism used when purchasing an App Store application.
macOS macOS (pronounced /ˌmækoʊˈɛs/;[6] previously Mac OS X and later OS X) is the current series of Unix-based graphical operating systems developed and marketed by Apple Inc. designed to run on Apple's Macintosh computers ("Macs"). It has been preinstalled on all Macs since 2002. Within the market of desktop, laptop and home computers, and by web usage, it is the second most widely used desktop OS after Microsoft Windows.[7][8]