The latest trend in operating system is the ability to connect with most devices. These is what is known as compatibility of the operating system.
The latest version of Apple's Mac OS X is 10.6.1 which is known as Snow Leopard.
The latest macOS is called "Sierra", a 64-bit OS.
For Windows, Windows 8.
For Mac, OS X Yosemite.
os stands for operating system.
Android
window 10
The standard OS for a PC is Windows, and the latest version is Windows 7.
The "latest" OS released by Microsoft is Windows Server 2008. The latest USER operating system is Vista.
Windows 7
win 8
Win 7
version 7
17.0.963.56
Apple- os x mountain lion is the latest operating system.
Meaning of open source OS
The latest version of Symbian OS is Nokia Belle and was released in August of 2011. It will be the last version as it was announced that Symbian would no longer be making smartphone technology.
The 5 "latest" OS's would likely all be various Linux and Unix or BSD based distributions. They update much quicker then windows or mac-os.
The latest version of Maya (2017) requires OS X 10.10.5 if that's what you mean.