What is a container in cloud computing?
A container packages an application together with everything it needs to run, like libraries and settings, so it behaves the same everywhere. Containers are lightweight because they share the host operating system instead of each running a full one. Docker is the most common tool, and containers make apps easy to move and deploy consistently.
Container versus virtual machine
A virtual machine includes a full operating system, which makes it heavy and slow to start. A container shares the host operating system and only packages the app and its dependencies, so it is small and starts in seconds.
- Consistent: runs the same on a laptop and in the cloud.
- Lightweight: shares the host OS, so it is fast and small.
- Portable: move it between environments easily.
The line interviewers want is containers are lightweight because they share the host OS, while VMs each run a full OS. That single contrast answers the most common follow up before it is even asked.
Common follow up questions
Related interview questions
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