- Package ID
A software-based online payment system
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.
- As of 11 November 2017, the total size of the BTC blockchain is 132.03 GB
- Size increases based on quantity of transactions (growth chart)
- Blockchain is slowly downloaded only when Bitcoin Core is running and connected to network
- Blockchain default location is
- This program should only be installed on a trusted machine.
- By default, upon first execution Bitcoin Core creates an unencrypted wallet file at
- Wallet.dat stores all your private keys for public Bitcoin addresses. If this file is not encrypted, anyone with access to the file may withdraw funds from addresses stored in the file. For this reason, you should encrypt the file as soon as possible with Bitcoin Core.
- After encrypting wallet.dat, back up wallet.dat to at least one other storage medium.
- More information about securing your wallet