The Ark delegates have the same function as witnesses in steem.
Only the top 51 delegate are creating blocks and get block rewards.
Public Ark delegates share a big part of their block rewards with their voters.

Delegate Ranking

Delegate Lists:

• https://www.arkcoin.net/delegates
• https://arkdelegates.io/
• https://explorer.ark.io/delegate-monitor
• https://forum.ark.io/category/5/delegates

Don't forget to vote with your Ark to support the delegates of your preference!