What is the principle of combining multiple containers inside a single Pod in Kubernetes?

In Kubernetes, multiple containers within a single Pod are grouped based on shared placement and lifecycle. All containers in a Pod run on the same host and share:

• Network: one IP address and ports
• Shared volumes for data storage

This allows containers within a Pod to interact efficiently, for example, one container can be the main application, and another — a sidecar that collects logs or updates configuration.

Example: A Pod with two containers — a web server and a logging container.

apiVersion: v1
kind: Pod
metadata:
  name: example-pod
spec:
  containers:
  - name: web-server
    image: nginx
  - name: log-agent
    image: fluentd

Thus, grouping containers in a Pod is based on shared resource usage and lifecycle, simplifying coordination and scaling.