Well Linux is most used server based Operating system and most back-end servers run Linux and knowing Linux commands is important to access the Linux terminal.

Basic Linux Commands:

pwd = print working directory
ls = list all the items in the directory
ls -l = list of all items with full detail (long format)
ls -a = list all the files including hidden
mkdir dir-name= create new directory(folder)
touch file-name = create new file
cat = view file contents
rm file-name = delete file
rm -r dir-name = delete dir
cp file-name copy-file-name = copy the file to another file
cp -r dir-name copy-dir-name = copy the complete directory
echo "text" > file-name = write in the file
    -by using echo we also create new file with text init

mv teste.txt tester.txt = rename the file
mv filename destination = move the file
less file-name = to view file
head file-name = print first 10 lines of the file
tail file-name = print last 10 lines of the file
head -n 5 file-name = print first n number of lines in the file ( here first 5 lines)
tail -n 5 file-name = print last n number of lines in the file ( here last 5 lines)
tail -f filename = print last 10 lines untill we stop by ctrl+c ( used for live logs)

grep word file-name = find specific word inside the file ( case sensitive)
grep -i word file-name = case insensitive search
grep -n word file-name = shows line number where that word exist
find . -name "filename" = find the file by name ( case sensitive)
find . -iname "filenmae" = case insensitive
find . -type -f = find the files
find . -type -d = find the directories
find . -size +1M = find the file with size more than 1mb 
find . -size -1M = find the file with size less than 1mb 
find . -name "*.log" -exec grep ERROR {} \; = Search text inside found files

Will it help me to become a Back-end Developer ?

Just learning Linux Commands won’t have you a Back-end Developer, Linux is just OS which is most used for servers , so learning it will help in the long run.

We need more than Basic Linux commands to be a Back-end Developer. Read the Article about what is Back-end Development?
The Article is Available at Becoming.

Docker is a containerization platform that packages applications into containers to run without any problem.

Before Docker/Containerization tool?

Before this for every application we use one whole server , which is so costly and difficult to maintain ,
so VMware solved that problem by using Virtual machines .

Even in Virtual Machines there are many flaws like,

• Dedicated OS for each application

• Not fast enough

• Dedicated storage

• Dedicated hardware & so on…..

Before Tools like Docker used in market , we have a Problem “IT works on my machine“.

Docker solved All the Problems.

Containers

Containers are collection of thing we need to run our applications.

It contains

• Base OS (mostly light weight OS)

• Infrastructure

• Container Engine

• Libraries needed to run the application

• Applications

Virtual Machines VS Containers

In Virtual Machines we need multiple OS to run multiple Application
But In Containers we just one OS for multiple Applications .

We use Container engine to run Multiple apps in single OS.

Installation

Windows

Install Docker Desktop + WSL from ( Windows OS ).

Mac

Install Docker Desktop from ( Mac OS ).

Linux

Install Docker Engine not Docker Desktop from ( Linux ).

Parts of Docker Desktop / Docker

Docker Runtime.

Docker Engine.

Docker Orchestration.

Docker Runtime

Basically allow us to Start/stop the container.

• runC (low level).

• containerD.

  • getting Data /internet.

  • manage runC.

Docker Engine

It contains Docker CLI , Rest API , DockerD(server) , Daemon .

Rest api is used to bridge between Sever and CLI .

Docker Orchestration

This manages the Containers .

Kubernetes is one of the orchestration tool.

Docker Images

Its a file that contains all the instructions to create a container for our applications.

We can Create Docker Images using Dockerfile.
We can Create Container using Docker Image.

Docker CLI commands

// docker run image-name
docker run hello-world

docker run - it will run the docker image if it is locally available or its download it from Docker Hub

docker images

docker images - it will return the available images locally

// docker pull image-name
docker pull ubuntu
//docker pull image-name:tag/version
docker pull ubuntu:16.01

docker pull - it will download the image from the Docker Hub
Note : if tag is not defined it will automatically download latest version

docker run -it ubunut

docker run -it ubuntu - its runs the image in interactive environment

docker ps
docker container ls

return all running containers

docker ps -a

return all the stopped containers

//docker rm container-id
docker rm 4f2304iua402j

docker rm - it will remove/delete the container

//docker rmi image-id
docker rmi 4239u020jasf9

docker rmi - it remove the docker image

Docker Layers

A Docker image is collection many files/layers

Each layers have a unique hash values as ID using “SHA256” representation.

If Two Docker images have same layer/file it will not download again from Docker Hub. it will use the already installed one for both images.

How to Create a Docker Image?

1. create a file named “ Dockerfile “ in the requires directory/folder.

2. write create instruction to run the container using Linux cmd’s.

3. Must declare a Base image(OS) in the file.

4. Write the instructions need to run the applications.

5. save the file.

//docker build -t image:tag/version path
docker build -t test-image:1.01 .

this command will build a docker image with file the mentioned directory , i mention “.” to use the same dir.

Is Docker needed for SDE roles in IT field today ?

Answer is Yes and No , because Docker is tool used by Devops people but in this modern time its will be useful to learn docker and Kubernetes to standout form the crowd while Appling for a job. Its not at all compulsory for Software Developer Role still today

Learning daily will make a big difference in a long run .
-rakeshraj .

What Sparked My Interest

Technology has always been all around me, but for a long time, I was just a user. I browsed websites, scrolled through social media, and used apps without ever thinking about how they were made. One day, while reading about how people were building amazing projects from scratch, something clicked. I thought, What if I could do that too?

I started watching YouTube videos, reading beginner guides, and playing around with free courses. The more I explored, the more I realized that coding is really about solving problems and creating things—and I’ve always loved both of those.

Why 2025 Was the Right Time

The world is changing fast. AI is everywhere. Remote work is more normal than ever. And tech skills are becoming the foundation for so many careers, not just traditional programming jobs. In 2025, learning to code feels more accessible than it’s ever been. There are free resources, beginner-friendly platforms, and communities that welcome newcomers like me.

On a personal level, I felt like it was time to challenge myself. I wanted to stop just thinking about doing something new and actually start. Coding gave me that opportunity.

What I Want to Build

Right now, my goals are simple. I want to understand how websites work. I want to build small projects, even if they’re messy or imperfect. Eventually, I’d love to create something useful—maybe a portfolio, a blog, or a tool that helps other people.

I’m starting with HTML, CSS, and JavaScript. I’m using free platforms like freeCodeCamp, The Odin Project, and YouTube tutorials. Every day, I learn something new, and every day, I realize how much more there is to discover—and that’s exciting.

To Anyone Else Just Starting: You’re Not Alone

If you’re thinking about learning to code, but you feel overwhelmed or unsure if you’re “techie” enough—trust me, I’ve been there. You don’t need to know everything to begin. You just need to begin.

We all start somewhere. And in 2025, there’s never been a better time to take that first step.