Printer Qestion

This is probably a stupid question but not knowing the answer is driving me crazy!

I had to buy a new printer today...my old one broke. I have never used it for art but letters and spitting out documents and such. I was going to buy just a simple printer but decided to get one that scans because I keep hearing that it is better to scan in artwork than photograph it....and in my case I would agree.

I have been thinking of doing some other stuff besides digital and the ability to scan it in will be nice.

I haven't opened the box so I don't know the dimensions exactly of the scanning surface...maybe 15 x 10 ...something like that.

Now I can understand how to scan something that size or smaller ...or even something bigger where you scan half and then scan the other half. ( I have heard of stitching programs so I sort of get that) But how do you scan a really large piece? I wouldn't want to do a large drawing or painting and then fold it. The whole thing makes no sense to me. Or do they sell really large scanners that would obviously cost a fortune to scan in a large 3 or 4 foot work?

I feel like there must be an easy answer here that is eluding me.