Copyright (c) 2009-2013 Bitcoin Developers
Distributed under the MIT/X11 software license, see the accompanying file COPYING or http://www.opensource.org/licenses/mit-license.php. This product includes software developed by the OpenSSL Project for use in the OpenSSL Toolkit. This product includes cryptographic software written by Eric Young (eay@cryptsoft.com), UPnP software written by Thomas Bernard and sphlib 3.0 by Thomas Pornin.
Quarkcoin is a free open source peer-to-peer electronic cash system that is completely decentralized, without the need for a central server or trusted parties. Users hold the crypto keys to their own money and transact directly with each other, with the help of a P2P network to check for double-spending.
You need the Qt4 run-time libraries to run Bitcoin-Qt. On Debian or Ubuntu:
sudo apt-get install libqtgui4