I talked about dockers and containers in one of my blogs:
https://leogether.blogspot.com/2020/08/docker-basics.html.
Now let's talk about what is Kubernetes and why do we need it?.
Containers are fast, reliable, light-weighted, and scalable.
You can easily scale 1 container to many containers but in the real world, there is a need that large organizations will scale multiple containers for an application, needed to ensure availability, load balancing, scaling up, and down based on the load. In such a situation you will need to manage containers like deploying, scheduling, scaling up and down, load balancing, monitoring in some automated way. For this reason, we need a container management tool.
Kubernetes is an opensource container orchestration tool/engine to automate deployment, scale, and manage the containerized application on a group of servers.
Docker is a containerization platform, and Kubernetes is a container management platform.