I dont know much about it but from what i do know its to do with emule which is a p2p software allowing you to connect to other people around the owrld to download and share files. the ed2k are the links to the files that you can download by using emule. be careful of what you download and which server you join as you might get your ass sued for downloading copyright material.
heres the offical site for it. only use this one as there are fakes sites out there that will charge you for downloading emule and may have spyware in it.
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