What does it mean if my version of Windows is no longer supported?
An unsupported version of Windows will no longer receive software updates from Windows Update. These include security updates that can help protect your PC from harmful viruses, spyware, and other malicious software, which can steal your personal information. Windows Update also installs the latest software updates to improve the reliability of Windows—new drivers for your hardware and more.

You should always install the latest service packs for Windows . You can download and install these through Windows Update.


Support end dates
Here are the dates when support will end for PCs running Windows XP.

•Support for Windows XP is ending on April 8, 2014.


Note
There's no SP3 for the 64-bit version of Windows XP. If you're running the 64-bit version of Windows XP with SP2, you have the latest service pack and will continue to be eligible for support and receive updates until April 8, 2014. To find out what version you're running, see Is my PC running the 32-bit or 64-bit version of Windows?

you've supplied the answer to your own question.

no software updates including security updates.

after April 8th 2014 you will not get these anymore.

you can still use the Windows XP operating system but any new
security exploits will not be plugged by microsoft.
also after April 8th 2014 if you buy a new printer for example
the manufacturer doesnt have to supply / support a driver for XP and microsoft doesnt have to come running to the rescue with a driver via windows updates.

I did not ask a question

@ movingtables

It is an informative post for Xp owners.

sorry the first line of your post confused me:

"What does it mean if my version of Windows is no longer supported?"

my bad.