Internet

Internet is one of the most revolucionaries inventions of the humankind, I think.

Its functions are to provide information and making the communication project much easier. But for me, the most cool thing of the Internet is that it makes everyone so close. Now that it's incredibly easy to speak with someone who's fore example living on the oposite side of the planet, you can feel like that people who's very far away from you, is also your closest friend.