Cryptocurrency, or digital currency, is an invention of the Internet. Basically, someone out there thought, "hey, what if we can create a system where money is not bound by geography, like the internet" and lo and behold, now we have over 3000 cryptocurrencies going around. Although bitcoin and ethereum tend to dominate the headlines when it comes to investing in cryptocurrencies, there are around 3000 crypto-assets in circulation, with more added all the time. Top cryptocurrencies list by exchange volume, rates of all currency pairs. Charts of the change in the exchange rate for the last week.
The top 10 cryptocurrency by market capitalization are Bitcoin, Ethereum, Ripple, Bitcoin Cash, Litecoin, EOS, Cardano, Stellar, NEO and TRON. These are all major players in the cryptocurrency space that have large communities and strong technological backing. There are many other smaller projects that might also be considered as part of the top 10 depending on how you measure it, but these are the largest ones by market cap.