Why does Chrome take up so much Memory?

i know why it dose best to do it in a example.

E.G. you look up a pic (tits for eg) it takes a few secs to load up when it dose and you close down your browser its pretty much saves it on your computer so the next time u look it up again it only takes a sec to load.

I dont know if you can disable this but i wouldent as it makes browsing thing faster. plus i have 8Gb and i have no problem at all. Internet issue?