i see everywhere online that you can use Messages app on mac book air and other mac computers, i have searched for over an hour and don't find it anywhere on my macbook air… please tell me where to find it, i also looked on the AppStore and it isn't available for download there (contrary to what the Apple WebSite suggested)
MacBook Air (11-inch Late 2010), Mac OS X (10.7.5)
Messages requires Mountain Lion or later: How to install OS X Yosemite on your Mac - Apple Support.
Messages requires Mountain Lion or later: How to install OS X Yosemite on your Mac - Apple Support.
The Message app is part of the Mac OS X when you have at least 10.8.5...with 10.7.5 it is iChat.
The two answers above are correct - just one additional comment:
You can see from this example how much you lose out on advances in software by not updating your operating system - in your case, for at least 3½ years.
There are numerous other examples. Look at these features just added by the last major OS X release (Yosemite in Oct., 2014):
can't find message application on my macbookair
