The other method to find your version is a command line method. There are two commands you can use:
or you can use
…and finally to find your kernel version and a few more details about your machine use the uname command which, per the man pages, shows system information. Examples:
uname -a : print all information
uname -r : print the kernel release
uname -v : print the kernel version
uname -o : print the operating system
You can see the current version of Ubuntu by selecting System > About Ubuntu. It's in the second paragraph.