Enderlist is a Minecraft Server list. It includes a database of many different Minecraft servers, ranked and filtered by certain categories such as votes and tags.
Votifier is a server plugin that allows server owners to know when you have voted for them. If a server supports Votifier you will be prompted to enter your Minecraft username when voting for a server. Server owners can enable Votifier when adding or editing a server. More information can be found on the official plugin page.
To add a server you must first create an account. Once you have done so log in and simply fill in your server details. You can only add a server if you are the owner or if you have been given permission by the owner.
Votes are reset for all servers on the 1st of every month to provide fair competition for newer servers.