Memory Terms

I have recently switched and am having a good time, one thing that I don't get is how OS X calls the memory. On a PC it said that it had virtual memory, real memory, and swap size. According to the iStat widget and activity monitor I have wired, innactive, free, active used and swap memory. What do all these mean?

Thanks for reading

Here's the scoop. I actually saved this from another post I saw on these forums some time ago, so if the author is reading this, please take a bow! I would give you credit if I could remember who you were! Anyway, here it is:

Wired Memory:
This is memory that applications or the system needs immediate access to, so it can't be cached to disk. It will vary depending on what applications you're using.

Active Memory:
This is memory that is actively being used.

Inactive Memory:
This memory is no longer being used and has been cached to disk. It'll remain in RAM until another application needs the space.

Free Memory:
This memory is not being used.

Your Mac's system tries to use as much RAM as possible thus keeping the 'free' RAM as low as possible since 'free' RAM is unused RAM and equals wasted RAM The OS also uses RAM for caching disk files as well as for storing the currently running apps & their data. The RAM that is currently available is more or less the sum of 'free' and 'inactive'. Whenever more RAM is needed, the system swaps out some of the current apps & their data to disk - this is reflected in the number of 'page-outs'.

Thanks guys for responding. I now get it. Isn't this a little more complicated than the PC method? (I don't want this to turn ugly). I think the PC is more straight-foward

To be perfectly honest cad2blender, I don't know...all this technical detail about RAM is something I don't really consider in my day to day usage.

I guess it would depend on what you are asking of your Mac to have to delve into this sort of statistical area.