eMule Shell Extension is a free, peer-to-peer or P2P file sharing application. Built on the eDonkey2000 network, it shares many features with its predecessor and adds more of its own into the mix. The original developer, Merkur, released the first version of the eMule client on May 13th, 2002. He was dissatisfied with the performance of the original eDonkey2000 client and therefore set out to create his own. He christened it eMule, in homage to the original eDonkey2000 client. With the program being open source, the network gradually grew and became one of the most reliable P2P networks available.
With the development of the client, several new features that were not available in the original eDonkey2000 client were created. Features developed include an integration of many networks into one. This creates one, large and very reliable network for the client to operate in. Files are all automatically checked for corruption, thus increasing the assurance of error-free downloads. Preview functions for media was also added. This allowed users to preview videos or audio even when downloads were still unfinished. This eliminates the risk of downloading bogus files with different, and possibly malicious content. There is also a built-in iRC client to allow peers on the network to interact with each other.