[Bitcoin Core](http://bitcoin.org/en/download) is the original Bitcoin client and it builds the backbone of the network. However, it downloads and stores the entire history of Bitcoin transactions (which is currently several GBs); depending on the speed of your computer and network connection, the synchronization process can take anywhere from a few hours to a day or more.
* See the documentation at the [Bitcoin Wiki](https://en.bitcoin.it/wiki/Main_Page)
for help and more information.
* Ask for help on [#bitcoin](http://webchat.freenode.net?channels=bitcoin) on Freenode. If you don't have an IRC client use [webchat here](http://webchat.freenode.net?channels=bitcoin).
The following are developer notes on how to build Bitcoin on your native platform. They are not complete guides, but include notes on the necessary libraries, compile flags, etc.
* Discuss on the [BitcoinTalk](https://bitcointalk.org/) forums, in the [Development & Technical Discussion board](https://bitcointalk.org/index.php?board=6.0).
* Discuss project-specific development on #bitcoin-core-dev on Freenode. If you don't have an IRC client use [webchat here](http://webchat.freenode.net/?channels=bitcoin-core-dev).
* Discuss general Bitcoin development on #bitcoin-dev on Freenode. If you don't have an IRC client use [webchat here](http://webchat.freenode.net/?channels=bitcoin-dev).