
Bitcoin uses decentralized, peer-to-peer technology to operate a public transactional database with no central authority or banks; managing transactions and the issuing of value units, called "bitcoins", is carried out collectively by the network. Bitcoin is open-source; its design is public, nobody owns or controls Bitcoin and everyone can take part. Through many of its unique properties, Bitcoin allows exciting uses that could not be covered by any previous payment system.
All transactions executed upon the Bitcoin network are public record. Bitcoin Core wallet allows creating private addresses, sending funds to private addresses, and synchronization of any private addresses that have received transactions. Bitcoin Core does this by reading the locally stored public ledger called the blockchain, and populating the user interface with these pertinent details. Bitcoin Core wallet will thus download a full copy of the distributed ledger to your computer and keep it updated. It will also keep it verified by comparing recent block data with block data of network nodes. A block chain is a transaction database containing all private addresses that have ever received a transaction. The database is shared by all nodes participating in a system based on the Bitcoin protocol. A full copy of a currency's block chain contains every transaction ever executed in the currency. With this information, one can find out how much value belonged to each address at any point in history.
New transactions are approved by computing a value determined dynamically by recent conditions of the Bitcoin network which satisfy conditions specified within the Bitcoin protocol. The Bitcoin protocol can only be modified by adjusting over 50% of currently running nodes, or in other words, upgrading to a new version. Most upgrades only modify the user interface and make no changes to the Bitcoin protocol. In the rare event a Bitcoin protocol update has been mandated, called a "hard fork", all software nodes that utilizes the Bitcoin blockchain must be upgraded by a certain date.
%AppData%\Bitcoin\data%AppData%\Bitcoin\wallet.dat