Bitcoin Core integration/staging tree
Bitcoin Core is the hugely active open-source software which enables users to have a Bitcoin node and a Bitcoin wallet that fully verifies payments. The open-source software can be accessed via GitHub and has been forked over 21 thousand times. This is software was released around the same time as the Bitcoin network code by Satoshi Nakamoto in 2009. The code is often referred to as a Satoshi client, with client referring to running a node.
The software offers benefits of security, privacy, and a user interface. The software is programmed to decide which blockchain contains the valid transactions and will only accept transactions from this blockchain. The Bitcoin Core software is updated via Bitcoin Improvement Proposals (BIPs) which is a development process which ensures that proposed updates go through a level of scrutiny and review before being implemented.
The code is accessed on GitHub but the official website for the project is Bitcoincore.org. The website has an active blog which covers development updates and topics related to using the software. The Twitter page for the Bitcoin Core Project has over 93,000 followers.