Virtual Machine
A virtual machine (VM) is a software-based emulation of a physical computer system that runs an operating system and applications as if they were on dedicated hardware. It abstracts physical resources like CPU, memory, and storage, allowing multiple VMs to operate independently on a single physical host. This enables efficient resource utilization, isolation, and portability across different environments.
Developers should learn and use virtual machines for tasks like testing software in isolated environments, running legacy applications on modern hardware, and creating reproducible development setups. They are essential in cloud computing for deploying scalable services, in DevOps for infrastructure automation, and in security for sandboxing potentially harmful code.