Container Registry Glossary

The DigitalOcean Container Registry (DOCR) is a private Docker image registry with additional tooling support that enables integration with your Docker environment and DigitalOcean Kubernetes clusters. DOCR registries are private and co-located in the datacenters where DigitalOcean Kubernetes clusters are operated for secure, stable, and performant rollout of images to your clusters.

This glossary defines the core concepts behind Container Registry to help build your mental model of how Container Registry work and understand what the documentation is referring to when it uses certain terminology.

A container image digest, image digest, or digest, is a unique, immutable identifier for a container image to deploy.
A container image, Docker image, or image, is a static file containing executable code that cannot be changed.
A load balancer distributes traffic across a backend pool of servers to improve the stability and responsiveness of an application.
A manifest file, or manifest, is a file containing metadata for a group of files that are part of a set unit.
A manifest list is a document that describes a container’s contents, loading sequences, points of origin, and points of destination.
Secrets are blobs of data, such as a password, which you do not want transmitted over a network or stored unencrypted.
Tags are keywords associated with resources which help with managing resource ownership and organize lookups and actions on resources.