What AWS service provides resizable virtual servers in the cloud?

Amazon EC2 provides resizable virtual servers in the cloud.

EC2 stands for Amazon Elastic Compute Cloud. Instead of buying and maintaining physical machines, customers launch virtual computers called instances and choose their operating system, processor, memory, storage, and networking settings. They can add or remove instances as demand changes, which explains the word “elastic.”

Amazon announced EC2’s limited public beta on August 25, 2006. Its pay-as-you-go model helped make infrastructure-as-a-service practical: developers could obtain computing capacity in minutes rather than wait for hardware procurement. Amazon Machine Images, or AMIs, let users create repeatable server configurations.

EC2 is often confused with neighboring AWS services. Amazon S3 stores objects such as files and backups, Amazon EBS supplies block storage for EC2 instances, and Amazon RDS manages relational databases. EC2 itself is the general-purpose compute layer, although many AWS services can run alongside or on top of it.