What is swap memory?

According to my istat pro widgit here I have some swap memory. I understand everything else in this pic but not the swap one. Is it related to video memory? If so why would it be 64MB and not the 128MB that's in my video card. This really puzzles me.

And here is a pic for reference.

Wouldn't that be what we used to call in the old days virtual memory?

The empty space on a hard drive is transformed in temp memory for a task being run by an app if RAM isn't sufficient or if the task is too CPU/RAM intensive.

Yep swap memory is the same as virtual memory. Say you have lots of programs open and there is to many instructions for your RAM, it will only take the current instructions its working on and needing for a program and store the rest in swap memory. This means each application will take up less RAM. When the instructions that are in the swap memory are needed they are swapped back into RAM.

Thank you both for the info. I used to fiddle with how much ram I allocated for my virtual memory in OS 8 and 9. Now I know this is the same thing basically I don't have to worry about it anymore.

swamp memory is something i would not want to rely on..it slows your rig up...get more memory