Your word processing program provides a good example. If you don't save them to the hard drive before turning off the computer, they're lost. The amount of memory you have in your computer definitely affects browsing speed, and everything else you do with your computer. You see, the more the data a computer can store in a RAM memory chip, the faster the computer works. Once the computer runs out of RAM, it starts using something called virtual memory, which means that it is actually using the hard drive.
Virtual memory is painfully slow.
It's kind of like taking your car off-road. You can still drive, you just can't go 75 MPH like you can on a four-lane freeway. Well, it depends on the size of the files you load, and the programs you run. Certainly 16 megabytes is enough to process a webpage. Webpages generally are not larger than half a megabyte.