Help understanding Page Ins and outs

I am trying to better understand this term I have heard mentioned here and there on the forum with regards to Page ins and Page out's - what does the page ins and outs do exactly?

I run alot of video through my MBP and during a video I did today here is what I got on the activity monitor.

Free: 15.0 MB VM size: 186.30 MB
Wired: 1.24 GB Page ins: 459.8 MB
Active: 3.97 GB Page outs: 15.7 MB
Inactive: 2.77 GB Swap used: 31.1 MB
Used: 7.98 GB


I would love to get a better translation of what this all means... and how it is taxing the system.


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2011 MacBookPro 8,2 - Intel Core i7 - 2.3 GHz - 8 GB ram

 

I have seen this on Wikipedia and am still a bit confused as to how the paging thing relates to the situation I have, thus the question for someone that has an intimate knowledge to break it down to something easy for a neophyte like me to grasp.

Thanks for adding this link to the thread, it is helpful to the overall question.

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Thanks for this link GGJ, this has helped me get a little greater grasp in understanding the Page in and outs.