There are hundreds of altcoins, and more appear every day. Most altcoins are little more than Bitcoin clones and they do not survive for very long. They only change minor features, such as its hashing algorithm, distribution method, or transactions speed. One exception is Litecoin, which has branded itself as silver to Bitcoins gold. The reason for that is that, in addition to using a different hashing algorithm than Bitcoin, Litecoin has a much higher number of currency units.