Everyone nowadays knows about bitcoin but very few know that there are thousands of virtual currencies.
you can check out the top 1000 virtual currencies here
https://coinmarketcap.com/all/views/all/
Any virtual currency other than bitcoin is an "alternative"coin or altcoin.
There is a lot of potential for them too and its a great time to collect some now.
It is now impossible to mine for bitcoin today without immense hardware.So mining other crypto-currencies that have a less difficulty and more potential to grow will be a great thing.
I am mining currently through cloud mining and learning to mine using cgminer/sgminer and still working on it. Please comment to know more :D
happy learning everyone :D