Masternodes primary function is to relay transactions across the network.
Additionally they carry out the anonymization of funds and enable double-spend-proof transactions through instant lockdowns.
In return for providing these services, one Masternode is selected by the network to receive a part of the reward of each mined block.
Additionally they carry out the anonymization of funds and enable double-spend-proof transactions through instant lockdowns.
In return for providing these services, one Masternode is selected by the network to receive a part of the reward of each mined block.
Rodrigo summed it up beautifully above.
There are a lot of websites out there which list what masternode coins there are, including their return on investment (ROI).
https://masternodes.pro/ is an interesting one, but be aware that they don't list ALL masternode coins, only ones registered to that site.
Personally, I have a Solaris masternode and as also mentioned in this post, they can be technical to set up (luckily I had help!).
Good luck out there.
-Knightly