Build Applications like a pro.

What is Docker ?

Docker is an open platform for developing, shipping, and running applications. Docker enables you to separate your applications from your infrastructure so you can deliver software quickly ( definition from docker website).

This probably sounds like gibberish to you right ? Don't Panic, It also made no sense to me once i first started learning about docker. But i'm going to explain it to you in "english".

Docker is a unix machine that is used to make containers and images for a certain application and break it down to microservices.

i think at this point it's safe to say that docker is used (but not limited) to creating microservices.

we will go through the other uses of docker in a bit. first lets see what developers used to build microservices before docker.

But microservices existed before docker ?

yeah, that's true.

microservices existed way before docker but they were installed using virtualization, multiple virtual machines were installed in a single hosting machine.

This had one major drawback.

It caused wastage of resources, since they could not maximize the usage of memory, processing power, disk space e.t.c .

This is where docker thrives at docker does not need pre-allocation of resources hence solving the memory leaks problems.

why Docker ?

If your still not convinced to start using docker here are a few reasons to atleast try it out.

• Helps you run consistent containers.

• You can use containers to run the app, independent of the resources you have on your local machine.

• You can also use docker to run your app on any platform, You run a container containing a virtual machine that has it's own operating system.

• intergrates well with continous intergration.

Dockerizing applications .

Dockerizing your applications is not a very hard task. However,it can be challenging depending on the complexity of your applications.

Nevertheless, it usually follows the same pattern which i will take you through.

step 1 : create a docker file

a docker file is a text document that contains all the commands a user could call on the command line to assemble an image.

step 2 : build an image.

an image is a file used to execute code in a docker container. Docker images essentially act as a set of instructions to run an application.

step 3 : run a container.

a container is an instance of an image, it is a lightweight, standalone, executable package of software that includes everything needed to run an application.

conclusion.

Hopefully, by now you have an idea of what docker is. In my next article i will take you through the steps of dockerizing a fullstack application.

Happy Coding Nerds!