Bitcoin Core is the original Bitcoin client and it builds the backbone of the network. It downloads and, by default, stores the entire history of Bitcoin transactions (which is currently more than 100 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).