Mavericks, named after a surfing spot in Northern California, was the first in a series of OS X versions named after locales in Apple's home state; previous releases had big cat names.
The 9th major release of macOS, Apple Inc.'s desktop and server operating system for Macintosh computers, is OS X Mavericks (version 10.9). OS X Mavericks was introduced at WWDC 2013 on June 10, 2013, and was released worldwide on October 22, 2013.
Battery life, Finder improvements, other improvements for power users, continuing iCloud integration, and bringing more of Apple's iOS apps to OS X were all highlighted in the update. Mavericks, named after a surfing spot in Northern California, was the first in a series of OS X versions named after locales in Apple's home state; previous releases had big cat names.
Since macOS X 10.1 "Puma," OS X Mavericks was the first major OS X update to be available as a free upgrade.
Apple revealed OS X Mavericks during its keynote at the Apple Worldwide Developers Conference (WWDC) on June 10, 2013. (which also introduced iOS 7, a revised MacBook Air, the sixth-generation AirPort Extreme, the fifth-generation AirPort Time Capsule, and a redesigned Mac Pro).
During a keynote on October 22, 2013, Apple said that 10.9 will be available for download on the Mac App Store immediately. Unlike previous versions of OS X, 10.9 will be free to all customers running Snow Leopard (10.6.8) or later.
On October 22, 2013, Apple announced that OS X and iWork upgrades would be free for the rest of your life.
If you do decide to continue with Mavericks, I recommend switching to a different browser, like Firefox, for security concerns. I'm not sure if Firefox is still supported in Mavericks, but it's probably a better alternative to Safari.
I recommend that you utilize High Sierra. HS operates flawlessly on my late-2012 iMac. I believe it is still compatible with Adobe CS6.
It continues to receive security upgrades, but this may come to an end in the fall. When that happens, you can use Firefox to browse the web, which will most likely be updated for at least the upcoming 3-4 years.
Also, don't assume you're limited to a single macOS version. You can have numerous boot disks, each with a distinct version of the operating system.
You could partition your internal drive and install various OS versions, allowing you to keep your old applications while benefiting from the security of a more contemporary OS.
Unless they've discontinued it since December, which is unlikely, Firefox is still fully supported on Mavericks. Everything works great with the latest version, including YouTube.
Is it a 21.5 or a 27-inch model? If it's the 27, you should upgrade the RAM to notice some improvements in online browsing and overall speed.
