Azureus is a bittorrent client which lets file-hungry downloaders share large files in an organized and highly efficient way. The majority of users may be more familiar with the well known eMule, and although the system it uses results in a more user-friendly experience, the engine used by Azureus can offer some alternative and vastly superior performance enhancements. The primary advantage of using a bittorrent client is the sheer speed at which files can be downloaded. Performance-wise, Azureus outstrips all the competition but of course, this comes at a price. The most widely discussed flaw of this software is the huge impact it has on your system's resources. The fact that it has been written in Java has been quoted as the source for its excess of memory usage, and in its attempt to optimize performance it squeezes every bit of bandwidth into getting files to download faster, making browsing the web a painfully slow experience. There is a wide selection of bittorrent clients available to choose from, so what makes Azureus stand out from the crowd? First of all, it's an open source project, which not only means that it's free to download but that there is a large community of programmers, designers and users who are continually testing and improving upon the latest release. In fact, the Azureus project community is so healthy that it recently won the Sourceforge Community Choice Awards for the "Best Overall" category, as voted by the users. To appeal to such a large user-base Azureus is packed with a great number of options, which can be used to customize precisely how the software runs. There are also comprehensive statistics about every file you download, with the all important "Estimated Time of Arrival" and the share ratio, which tells you how much of a particular file you have uploaded or "given back" to the community. Incidentally, in the perfect P2P community, every file should have a share ratio of two. (In other words, for each file you download, two users download it from you). What makes a bittorrent client different to a P2P client such as eMule, is that you must download a reference file, or torrent, from the Net, and open it in the client, as opposed to searching directly for the file within the software. A downside to this is that the reference files may linger on after the file they refer to has been removed from your computer. With that in mind, torrent files often come with a health rating, judged by how many sources there are for that file. Very often, the file will be available to be downloaded very quickly when it is first released but within a few weeks or months, will become either very slow or unavailable. Azureus is probably our favourite file sharing client but we prefer to use it alongside eMule as they both perform well under different circumstances. If you want to convert your Mac in to a download factory then Azureus is what you need, but if you prefer an easy life and aren't put off by the long waits, then stick with eMule.