backtrack hydra problem

Hi, im quite new to the blackhatworld, but i've messed alot with backtrack. I know already how the sniff-spoof tools and related work, but i'd like to have some information of the hydra program. I haven't found any guides or tutorials yet and I didn't understand much from posts on other forums except you can use it for pass attacks with dictionaries on router passes. Are there other uses? Please help me with some info about hydra. thanks for reading and sorry about my messed english=)

backtracker

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