A brief history
Founded in 2014 and launched in 2015, Stellar is operated by the Stellar Development Foundation, a nonprofit organization founded by Jed McCaleb. Stellar is a blockchain that makes payments easier by enabling its users to create, send, and trade digital representations of all forms of money, from fiat currencies like dollars and euros to cryptocurrencies like bitcoin. It aims to bring the world's finance systems together on a single network. As a cross-border transfer and payment system that connects financial entities, Stellar aims to significantly reduce transaction costs and speeds. While Stellar works similarly to technologies like Bitcoin, it distinguishes itself through its consensus protocol. The Stellar Consensus Protocol (SCP) is a “federated Byzantine agreement system” that allows decentralized, leaderless computing networks to efficiently reach a consensus outcome on some decision. The Stellar payment network uses SCP to provide a consistent view of the network’s transaction history to all participants.

XLM in practice
Lumens are most often used to pay transaction fees on Stellar, and to act as the intermediate currency that allows for the quick execution of trades. A built-in protocol automatically converts money sent through Stellar to Lumens and then to the desired coin. For example, if you send a payment in U.S. dollars to a recipient in Japan, Stellar converts the payment to Lumens, and the recipient can receive the payment in Yen. XLM also acts to create a small barrier to entry to the Stellar network to deter bad actors from slowing it down. In order to use the Stellar network, users are required to have a minimum balance- currently set at one Stellar lumen. There’s also a minimum transaction fee of 0.00001 Lumen. It should also be noted that Lumens cannot be mined and that instead, the Stellar Development Foundation released 100 billion Lumens in 2014 when the network went live- but was later voted to be cut down to 50 billion.