Hi
Can anyone tell me why my computer keeps coming up with a sign - vitual memory very low , windows is increasing, why is it very low and what can i do about it please.
is it anything to do with the ram as i think that is low also- (computer is 6 years old .)
but still working !
appreciate any replies.

Virtual memory is the space set aside on your hard drive where Windows stores things to transfer in and out of the RAM.
More RAM would be a plus [very cheap now, if you can find what your computer requires-6 years is an eternity in the computer world].  
The hard drive available space may be getting tight, that's why you keep getting the message. A larger drive or a second drive would alleviate that problem.

   Another reason is that you may have too many programs open.  The more programs you keep open, the more virtual memory is needed.  A temporary fix may be to close programs when you are not using them, but you should look into the things that dlwolff0 suggests above as more permanent fixes.