Node or Pod

node is simple server or virtual server it’s a smallest unit of k8s it used to run container like dockers. usually 1 app in 1 pod.

Service

permanent IP address. even if pod dies service stays.

• External Service
• Internal Service

Ingress

for domain name mapping

Config Map

external config of your app.

Secrets

used to store credentials. not in stored in plain text, base 64 encoded.

volumes

if your app generates some data, and app is restarted then data is gone. to prevent that we can use k8s volume, it attaches the on server hard drive folder, or some cloud storage.

Deployment

it’s a blueprint of your pods it’s an abstraction of your pods.

StatefulSet

specifically for applications like databases. like psql or mongo should be created using statefulSet. replicating the pods with same state. However, its make it tidies to solve it db’s should be hosted outside the k8s.