Stellar is working on to ease cross-borders transactions across the globe through blockchain technology. It is designed to support any form of currency.
Developed in 2014 by Jed McCaleb, Co-founder of Cryptocurrency: Ripple & Cryptocurrency Exchange : Mt.Gox, Stellar network is a non-profit decentralized open source blockchain.
Simply put Stellar is the shortened name for Stellar network. Stellar network itselfs contains Lumens through “stroops” to process transactions much like Etherium contains Ether through “gas” to process smart contracts.
XLM is the ticker symbol of “Stellar Lumen” that you will see on exchanges. Lumens is a Utility token or Cryptocurrency that use in the Open-source International Banking network called “Stella”