Bitcoin was created in 2009 by an anonymous individual who went by the name of Satoshi Nakamoto. His original paper on the technology can be found here and I highly suggest you read it after you finish this guide.
Bitcoin is a groundbreaking new technology that uses math to create a trustless public ledger. This public ledger is called the blockchain and it can be viewed in its entirety at anytime by anyone. This system essentially allows the transfer of any type of property between two people without relying on a third party such as a company or government. All different types of information can be stored in the blockchain, including but not limited to ownership of assets such as houses or stock shares, timestamping of important data, proof of identity,trustless lotteries, and votes. This technology isn’t just about digital cash, it’s about trustless transfers of all kinds through the internet, securely and decentralized.
The network runs in a similar fashion to other Peer2Peer technlogies such as bittorrent and folding@home, all transactions are processed by computers running the Bitcoin software and with their own copy of the blockchain. Those computers can be located in personal homes, corporate server farms, or anywhere else: they just need to be connected to the internet and running the Bitcoin software.
The properties of bitcoin and it’s blockchain are set in the code of the software that makes up the backbone of the network. To change this code, a majority of the people running the software must update to a new version of the client.
If you have the skillset required, you can easily access and interface with the blockchain using the Bitcoin software. For normal users, you can use block explorers powered by independent companies such as BlockChain.info and Blockr.io, which not only allow you to view transactions in real time, but also allows you to look at every transaction that has ever occurred in the history of Bitcoin.