These are the ff. Altcoins according to their ranks.
1. Ethereum - world’s first blockchain supercomputer
2. Bitcoin - first hard-forked cryptocurrency
3. Ripple - cross-border payment platform
4. Litecoin - confirm transactions faster, and utilizes scrypt as proof-of-work algorithm.
5. Dash - open-source p2p cryptocurrency
6. Ethereum Classic - decentralized software platform featuring Smart Contracts
7. BitConnect - can be exchanged directly between its community members without a central crypto asset exchange.
8. Zcash - built to secure your payment history
9. Monero - advertises itself as the ‘Private Digital Currency’
10. Neo - smart-economy software platform
11. BitShares - offers much more features than just smart contracts
12. Namecoin - blockchain-based domain registrar
13. Siacoin - decentralized cloud storage platform
14. Komodo - packed with best features of other coins.
15. Steem - social media platform that encourages people to share interesting content and get rewarded.
>But if you want you can check it in the google to know more about altcoins there are so many infos about the altcoins.
Already answered all here. answer most definitely ethereum. I also agree that. with blockchain their model erc20 and used even almost all altcoin, ethereum King technology blockchain at this time. may already described edge of some of the order of altcoin I quote above. ethereum be leading with their technology today.