Facts About Docker!

• Docker is a software platform that simplifies the process of building, running, managing and distributing applications. 
• Docker applications run in containers that can be used on any system: a developer's laptop, systems on premises, or in the cloud.
• Docker enables you to separate your applications from your infrastructure so you can deliver software quickly.
• Some Advantages of Docker is - cost savings, Compatibility & maintainability, Continuous deployment & testing, Rapid Deployment, Time saving etc.

What is Docker Image?

• A Docker image is a file used to execute code in a Docker container.
• Docker Images describe the applications and how they can be run.
• Docker images act like a template, which has set of instructions to build a Docker container.
• Docker image is comparable to a snapshot in virtual machine (VM) environments.

What is Docker Container?

• Docker is an open platform for developing, managing, and running applications.
• A Docker container image is a lightweight, standalone, executable package of software that includes everything needed to run an application like code, runtime, system tools, system libraries and settings.
• It is instance of the Image.

Difference between Docker Image and Container
Images describe the applications and how they can be run where as Containers are the image instances, where multiple containers of the same image can be run, each in a different state.

What is Docker Hub?

• Docker Hub is a service provided by Docker for finding and sharing container images with your team or anyone.
• In another word, Docker Hub is the world's largest. library and community for container images.
• rowse over 100,000 container images from software vendors, open-source projects, and the community. postgres. Official.
• Key features include: Private Repositories: Push and pull container images. Automated Builds: Automatically build container images from GitHub and Bitbucket and push them to Docker Hub.

What is Docker Registry?

• A Docker registry is a storage and distribution for Docker images.
• A service responsible for hosting and distributing images.

What is Docker Engine?

Docker Engine is an open source containerization technology for building and containerizing your applications.
Docker Engine builds and run containers using docker components and services.
Docker Engine supports the tasks and workflows involved to build, ship and run container based applications.

What is Docker Client?

• The Docker client is medium for Docker users to interact or connect with Docker.
• When you use commands such as docker run , the client sends these commands to dockerd , which carries them out. The docker command uses the Docker API. The Docker client can communicate with more than one daemon.

What is Docker Deamon?

• The Docker daemon or dockerd listens for Docker API requests and manages Docker objects such as images, containers, networks, and volumes.
• Docker daemon directory -By default this directory is: /var/lib/docker on Linux. C:\ProgramData\docker on Windows.
• A daemon can also communicate with other daemons to manage Docker services.

What is Docker Swarm?

• A Docker Swarm is a group of either physical or virtual machines that are running the Docker application and that have been configured to join together in a cluster.
• Docker Swarm offers automatic load balancing
• Docker Swarm's load balancer runs on every node and is capable of balancing load requests across multiple containers and hosts.

What is Docker Compose?

• Docker Compose is a tool for defining and running multi-container Docker applications.
• Docker compose use YAML file to configure your application's services.
• with a single command, we can create and start all the services from your configuration.
• Docker compose helps if you want to create more than one container for your application, you have to create several Docker files and adds on the load of maintaining them and is also quite time-consuming, so compose rid this things.

What is Docker Machine?

• Docker Machine is a tool for managing your Dockerized hosts (hosts with Docker Engine on them).
• Docker Machine is a tool that lets you install Docker Engine on virtual hosts, and manage the hosts with docker-machine commands.
• Docker Machine has its own command line client docker-machine and the Docker Engine client, docker.

What is Docker For windows?

• Docker is an open-source project for automating the deployment of applications as portable, self-sufficient containers that can run on the cloud or on-premises.
• You can run both Linux and Windows programs and executables in Docker containers.
• You can run both Linux and Windows programs and executables in Docker containers.

What is Docker ToolBox?

• Docker Toolbox is an installer for quick setup and launch of a Docker environment on older Mac and Windows systems that do not meet the requirements of the new Docker for Mac and Docker for Windows apps.

What is Docker kitematic?

• Kitematic is a simple application for managing Docker containers on Mac, Linux and Windows.
• Kitematic automates the Docker installation and setup process and provides an intuitive graphical user interface (GUI) for running Docker containers.
• Kitematic integrates with Docker Machine to provision a VirtualBox VM and install the Docker Engine locally on your machine.

What is Docker Enterprise?

• Docker Enterprise Edition (Docker EE) is designed for enterprise development and IT teams who build, ship, and run business-critical applications in production and at scale.

Docker Enterprise features

• Kubernetes orchestration full feature set.
• CNCF Certified Kubernetes conformance.
• Kubernetes app deployment via UCP web UI or CLI ( kubectl )
• Compose stack deployment for Swarm and Kubernetes apps ( docker stack deploy )
• Role-based access control for Kubernetes workloads.

What is Amazon ECS?

• Amazon Elastic Container Service (ECS) is a highly scalable, high performance container management service that supports Docker containers and allows you to easily run applications on a managed cluster of Amazon Elastic Compute Cloud (Amazon EC2) instances.
• Amazon ECS uses Docker images in task definitions to launch containers.
• Amazon ECS allows you to easily deploy containerized workloads on AWS.
• You can use it to run, stop, and manage containers on a cluster.
• It Can use to run and maintain a specified number of tasks simultaneously in a cluster.

What is Google Container Engine?

• GKE provides a managed environment for deploying, managing, and scaling your containerized applications using Google infrastructure.
• Google Container Engine is powered by the open-source Kubernetes system that Google originally created to help the company in its own operational management of containers, and it can be deployed for use on on-premises, hybrid cloud or public cloud infrastructure.