[Bitcoin-Qt](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.
Unpack the files into a directory and run bitcoin-qt.exe.
### Need Help?
* 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 guide, but include notes on the necessary libraries, compile flags, etc.
The Bitcoin repo's [root README](https://github.com/bitcoin/bitcoin/blob/master/README.md) contains relevant information on the development process and automated testing.