Bitcoin Core – Bitcoin Wiki
Bitcoin Core (formerly Bitcoin-Qt) is the third Bitcoin client, developed by Wladimir J. van der Laan based on the original reference code by Satoshi Nakamoto.  [Two] [Three] It has been bundled with bitcoind since version 0.Five. [Four] Bitcoin-Qt has been rebranded to Bitcoin Core since version 0.9.0 [Five] .
Bitcoin Core can be used as a desktop client for regular payments or as a server utility for merchants and other payment services.
Source code (and build instructions for supported platforms) can be found at the Bitcoin GitHub page.
- Compatibility with Linux (both GNOME and KDE), Mac OS X and Windows
- All functionality of the original wxWidgets client
- Asks for confirmation before sending coins
- CSV export of transactions
- Clearer transaction list with status icons and real-time filtering
- Progress bar on initial block download
- Languages: Dutch, English, German, Chinese and many more. Translations are being done by volunteers on Transifex.
- Sendmany support in UI (send to numerous recipients in one transaction)
- Numerous unit support, can display subdivided bitcoins (mBTC, µBTC) for users that like large numbers (only decimal units)
- Splash screen that details progress
- Debug window
- Payment requests (BIP 70)
- Coin control
- bitcoin-cli as a RPC client, instead of bitcoind executable functioning both as a server and as a RPC client
Bitcoin Core is often criticized for being slow in downloading and verifying the Bitcoin transaction database (the blockchain). The download may be quicker using the bootstrap method. NOTE: As of version 0.Ten.0 it is now slower to download the blockchain via the torrent than it is to download the utter blockchain through the P2P client.
It has also been criticized for “hogging” upload bandwidth when peers connect to download the blockchain (possible only when run with port eight thousand three hundred thirty three accessible to outside connections). This perceived “issue” has been discussed extensively on GitHub. Most modern routers support quality-of-service that can be configured to decently share the internet connection across all services, and even deprioritise Bitcoin traffic. Bitcoin Core includes a script for Linux to configure QoS on an individual host.  Windows users can also use third-party software such as Netbalancer to throttle the application’s upload bandwidth and ensure that one has enough upload bandwidth available for regular computer and internet use to be unaffected.