Docker is an open-source platform that enables developers to build, package, and deploy applications in lightweight, portable containers. These containers include everything needed to run an application—code, libraries, and dependencies—ensuring consistency across different environments. Docker eliminates the “works on my machine” problem by providing a standardized runtime, making applications easily scalable and portable across cloud, on-premise, and hybrid infrastructures. With its fast deployment, efficient resource utilization, and seamless integration with CI/CD pipelines, Docker has become an essential tool for modern DevOps workflows, streamlining software development and deployment with speed, flexibility, and reliability.