Magento is an open source eCommerce platform launched in 2008. It provides features such as multi-store functionality, third party application integration, SEO friendly stores, multiple payment gateways, and sales reporting. The latest version (1.9) includes improvements such as responsive design, address checkout, security enhancements, and fixes for promotional pricing and payments. Magento is widely used due to its flexibility, scalability, and user-friendly admin interface.