The Google calculator is included in Google.com's normal web search. So instead of entering words you want to find in web pages, you can simply enter math queries like the following:

10 + 7 * 3 – 12

The Google result will then display the solution: "10 + (7 * 3) - 12 = 19." That's already a little more fun than using a normal calculator (and incredibly helpful too, at times), but there's much more to it. Let's start with an Easter Egg – a hidden function within a program that makes it do something unexpected and interesting – and enter the following:

answer to life, the universe and everything

Entering this will result in the Google calculator showing you the answer "42." This is a reference to a mythical number from Douglas Adams' sci-fi opera "The Hitchhiker's Guide to the Galaxy." I won't spoil its meaning here, but instead suggest you simply read this great book (or, watch the movie). This isn't the only connection between Google and Douglas Adams, by the way. Completely coincidentally, the word "Googleplex" – the name the Google employees gave their California headquarters – appeared in the Hitchhiker's Guide:

"And are you not," said Fook leaning anxiously forward, "a greater analyst than the Googleplex Star Thinker in the Seventh Galaxy of Light and Ingenuity which can calculate the trajectory of every single dust particle throughout a five-week Dangrabad Beta sand blizzard?"

The calculator fun doesn't stop there. The following are just some more examples of what's possible, and often these different queries can be combined to larger formulas:

seconds in a year (result: 31,556,926 seconds)

15 USD in EUR (12.74 Euro)

120 pounds * 2000 feet in Calories (77.77 kilocalories)

furlongs per fortnight (0.000166309524 m / s)

speed of light in knots (582,749,918 knots)