DC++ – is a free and open-source, peer-to-peer file-sharing client that can be used to connect to the Direct Connect network or to the ADC protocol. It is developed primarily by Jacek Sieka, nicknamed arnetheduck.
As of 2008, DC++ had around 90% market share of the Direct Connect community.
DC++ is a free and open-source alternative to the original client, NeoModus Direct Connect (NMDC); it connects to the same file-sharing network and supports the same file-sharing protocol. One of the reasons commonly attributed to the aforementioned popularity of DC++ is that it has no adware of any kind, unlike NMDC.
Many other clients exist for the Direct Connect network, and most of these are DC++ “mods”: modified versions of DC++, based on DC++’s source code. A partial list of DC++ mods is given below. Some of these clients were developed for specialized communities (e.g. music-sharing communities), or in order to support specific experimental features, or perhaps features that have been rejected from inclusion in DC++ itself. An example of an experimental feature is hashing, which was initially implemented in BCDC++ and later adopted by DC++.