How to View File Contents Using cat

How to View File Contents Using cat

Hey there! 👋 Welcome back to ProgramGuru.org, where we simplify Linux for absolute beginners. In this lesson, you're going to learn one of the most basic but powerful commands in the Linux world — cat.

Let’s say you have a file and you just want to peek inside it. Not edit it, not change anything—just look. That’s exactly what the cat command does.

🔹 What is cat?

cat stands for “concatenate” — but don't let that word scare you. Most of the time, we use cat to simply view the contents of a file.

🔹 Basic Usage

Let’s start with a very simple example. Imagine you have a file called notes.txt. To view its contents, you just type:

cat notes.txt

And the output might look something like this:

This is my Linux learning journal.
Day 1: Learned about files and directories.
Day 2: Discovered the magic of the cat command!

🔹 Create a Sample File (if you don’t have one)

If you don’t have a file yet, let’s make one quickly:

echo "Hello, Linux world!" > hello.txt

Now view it:

cat hello.txt

Hello, Linux world!

🔹 View Multiple Files

You can also view multiple files at once. Just separate them by space:

cat file1.txt file2.txt

🔹 Number the Lines in the Output

To number each line, use the -n option:

cat -n notes.txt

     1  This is my Linux learning journal.
     2  Day 1: Learned about files and directories.
     3  Day 2: Discovered the magic of the cat command!

🔹 Caution with Large Files

If the file is huge, cat will dump everything at once. In such cases, it’s better to use less or more. We’ll cover those in another tutorial!

🔹 Summary

So, whenever you want a quick look at what’s inside a text file — whether it's logs, notes, or config files — just say:

cat filename.txt

And you're done!

That’s it for this one. You just took one more step toward Linux mastery. 🚀 Keep going — we’ve got many more awesome commands to explore together!