Complete guide — Docker explained: images, containers and volumes
Everything you need to know
Three concepts for repeatable environments without confusing runtime and persistent data.
Image: the packaged application
An image packages application files and runtime dependencies. A Dockerfile describes its build. Pin important versions and keep it small. Test this repeatable artifact and deploy it rather than manually recreating each server environment.
Container: a running instance
A container runs an image with its own processes and configuration. Several containers can share one image. They share the host kernel, unlike full virtual machines. Supply configuration at runtime and never bake secrets into image layers.
Volume: data that must survive
Deleting a container removes its writable layer. Store database files and uploads in a suitable volume or external service. Persistence is not backup: schedule backups and test restoration. Replace the app container to verify data survives.
Key takeaway : Build images, run containers and manage persistent data separately.
Why Tuplify Studio?
We containerize web apps and APIs, configure Docker deployments and prepare health checks and backups.
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Tuplify Studio turns these concepts into working software.
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