Building large-scale applications often demands more RAM, CPU, and storage than physical servers can cost-effectively provide. Cloud computing solves this by letting you rent resources on demand. Amazon Web Services (AWS) is a leading provider, with its Elastic Compute Cloud (EC2) being a core service for virtual machines.

In cloud terms, a virtual machine is an instance. AWS offers many instance types, like the free-tier t2.micro, to match hardware needs. You then select software via an Amazon Machine Image (AMI), a preconfigured template. The workflow involves configuring networking, storage, and security before launching.

Once launched, developers connect via SSH to deploy applications. EC2 allows both vertical scaling (changing instance size) and horizontal scaling (adding instances). This flexibility makes it a foundational tool for managing application lifecycles and adapting to changing workloads efficiently.