Satoshi Nakamoto, the internet mystery.
Satoshi Nakamoto is the name used by the presumed pseudonymous person or people who created bitcoin, the first peer-to-peer digital currency that prevents double-spending and is not owned by a single authority. Satoshi stated that he/she/they started the bitcoin development in 2007. On 18 August 2008 a colleague registered the domain name (bitcoin dot org) from anonymousspeech, a domain registrar that promises anonymity during purchase. After that, Nakamoto published the whitepaper in which he/she/they explained a new form of electronic cash without having to rely on third parties.
On 31st of October 2008, Satoshi sent the first email on "The Cryptography Mailing List", explaining what is bitcoin. Those people seemed to be really interested on such idea, and thus, they were the very first bitcoin users. Satoshi was trying to make the program look as good as he could, by fixing bugs, changing stuff in the code etc. He is considered genius because he was the first one that solved the double-spend problem, using a chain of blocks as he wrote in the white paper. Block number 0, also known as genesis block, contains a text Satoshi chose to leave. Specifically it says "The Times 03/Jan/2009 Chancellor on brink of second bailout for banks". Another reason people admire him is because he created a form of wealth that has no central authority to control the transactions. Literally, no one controls the bitcoin network, which makes it a safe place for storing wealth. It has been characterized as electronic gold.
He is entirely unknown outside of Bitcoin as far as anyone can tell, and his (never used) PGP key was created just months prior to the date of the genesis block. He seems to be very familiar with the cryptography mailing list, but there are no non-Bitcoin posts from him on it. He has used an email address from an anonymous mail hosting service (vistomail) as well as one from a free webmail account (gmx.com) and sends mail when connected via Tor. Some have speculated that his entire identity was created in advance in order to protect himself or the network. Perhaps he chose the name Satoshi because it can mean "wisdom" or "reason" and Nakamoto can mean "central source".
It's possible that Nakamoto holds a huge amount of bitcoins since he was the first miner of the network. He logged off in December 13 of 2010 and never logged back in on bitcointalk, a forum he made. His last known activity was on 23st of April 2011 when Mike Hearn asked him (via email) if he had thought of coming back to the community. Satoshi replied that he moved on to other things. Later, Gavin Andresen, the person that continued the bitcoin development after Satoshi's departure, sent him a message saying that CIA is interested on the project and they wanted to invite them to an event. Satoshi never went.
Since then, many people have claimed of being Satoshi Nakamoto, although none of them has been verified. In order for someone to prove that is Satoshi, will have to sign a message from the rewarded address of the genesis block (1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa) or provide a signed message with a digital signature of his known PGP public key.