Google Does Math!

I don't remember how I found this out, but sometime last week I stumbled upon the fact that Google does math! I have not tested it thoroughly, I only fiddled with it for 5-10 minutes, but it seems that this only works if you type the math problem in the little search box in the upper-right corner of your browser (and of course you must have Google selected as the search engine). I guess this is best explained using an example. If you type in "2 + 2" (without the quotes), it will pop up with suggestions, like normal, but the first suggestion will be "= 4". You could also write it as "2 plus 2". You cannot, however, write out the numbers in word form, like "two plus two". Only numbers work. This works with subtraction, multiplication ( * ), and division ( / ) too. It even works with exponents ( ^ ) and roots (the symbol for roots would be ^ as well, except you would use fraction powers. square root of 4 would be 4^(1/2) ). All these work in word form as well. It also does sine, cosine, tangent, cotangent, arcsine, etc. I have not found a way to make it do derivatives and integrals, so I don't think those work.
Anyway, this has made me wonder why Google decided to add a calculator to their search engine. What is the point? Maybe just because they could. Maybe to bug the people who figure it out, like me.
Since this post is about Google, I feel obligated to talk about googol. A googol is an actual number, 10 raised to the 100th power. That is, a one with one hundred zeros after it:

100000000000000000000000000000000000000000000000000
00000000000000000000000000000000000000000000000000

A googolplex is even bigger. It is a one with one googol of zeros after it. I can't even imagine trying to write that out. So, I don't know if Google got its name from the googol, but it probably did, since Google searches googols of websites to find the ones you want.