Magento 2 can be considered as the latest incarnation of Magento which is a leading enterprise-class eCommerce platform. Inheriting numerous success factors of the previous versions of Magento, Magento 2 also presents modern technologies and structure, and modified directory structure but takes it to a whole new level, more simplified customization. At present, there are over 200,000 online retailers who use the Magento 2 platform.
Source: File Structure in Magento 2 – Mageplaza