Amazon EC2 is a core cloud computing service that allows users to create and manage virtual servers, known as instances, on demand in the cloud instead of maintaining physical on-premise hardware. With EC2, organizations can quickly launch servers with different instance types based on their needs for CPU, memory, storage, or GPU power, and they can scale resources up or down depending on application demand. Features such as scalable compute capacity, customizable security groups, flexible pricing models, and deep integration with other services from Amazon Web Services make EC2 a popular choice for hosting applications and workloads. Companies commonly use EC2 to run web applications, development and testing environments, data processing tasks, and large-scale infrastructure while maintaining flexibility, high availability, and cost efficiency because they only pay for the computing resources they actually use.