While we may not know who he was, we know what he did. He was the inventor of the Bitcoin protocol, publishing a paper via the Cryptography Mailing List in November 2008. He then released the first version of the bitcoin software client in 2009, and participated with others on the project via mailing lists, until he finally began to fade from the community toward the end of 2010. He worked with people on the open source team, but took care never to reveal anything personal about himself, and the last anyone heard from him was in the spring of 2011, when he said that he had “moved on to other things”.

Satoshi Nakamoto is a person or group of people who created the Bitcoin protocol and reference software, Bitcoin Core. In 2008, Nakamoto published a paper on The Cryptography Mailing list at metzdowd.com describing the Bitcoin digital currency. In 2009, he released the first Bitcoin software that launched the network and the first units of the Bitcoin currency, called bitcoins.

Nakamoto is said to have continued to contribute to his Bitcoin software release with other developers until contact with his team and the community gradually began to fade in mid-2010. Near this time, he handed over control of the source code repository and alert key functions of the software to Gavin Andresen. Also around this same time, he handed over control of the Bitcoin.org domain and several other domains to various prominent members of the Bitcoin community.

Nakamoto is believed to be in possession of roughly one million bitcoins. At one point in December 2013, this was the equivalent of US$1.1 billion. Nakamoto's true identity remains unknown, and has been the subject of much speculation. It is not known whether the name "Satoshi Nakamoto" is real or a pseudonym, or whether the name represents one person or a group of people.

Sumber: Wikipedia & Coindesk