To begin a NODE is a server or computer device that stores and or maintains a network. If the computer, phone or any device can send , receive or transmit to the blockchain it is considered a node.
Masternodes, takes this one large step further. It performs functions that the regular node cannot. The Masternode is a computing device that contains the entire blockchain for that particular cryptocurrency.
As well, those that run the masternodes receives rewards for maintain the safety, security and verification of transactions. Yes, you can run your own node if you want to. You will be required to to purchase a certain amount of coins/tokes and then stake them or store them to support the blockchain. These coin have to remain there through the duration of the running of the masternode. You are paid a reward daily for running the node. This a great way to create a passive income. An additional perk of running a masternode, is the ability to have a say so in the running of the entire network. You are allowed to vote on important decision and updates or changes. If you want to delve deeper into the Masternodes a great place to start
is at: masternodesonline.com