Hi,

i would to know, what are the main importatnt alternative cryptocurrency to bitcoin??? example: litecoin, megacoin.....

- Why these kind of coin have need to exist? because bitcoin have some problem, or issue, and this type of coin are born to resolve this issue, or for another mission?

- this other coin can work with the same process of bitcoin (blockchain, private and pubblic key, process of mining??)

- the alternative cryptocurrecy can be considered a true alternative of bitcoin or these are weak to challege bitcoin??

Thanks