Bash Basics: touch, Variables, export, and File Viewers

Today I learned a mix of small but very useful Linux/Bash basics — creating multiple files at once, working with variables, and the difference between two common file-viewing commands.

Creating Files with touch

The touch command creates empty files (or updates the timestamp if the file already exists).

Creating files one by one

touch preven1 preven2 preven3

This creates three separate files: preven1, preven2, and preven3.

Creating a series of files using brace expansion

Instead of typing each file name manually, you can use { } (curly braces) to generate a range automatically:

touch preven{1..5}

This creates 5 files at once: preven1, preven2, preven3, preven4, preven5.

You can even combine two ranges together:

touch preven{a..d}{1..5}

This creates every combination of letters a to d with numbers 1 to 5 — so prevena1, prevena2 ... all the way to prevend5 (20 files in total). This is called brace expansion, and it saves a lot of typing.

Variables in Bash

A variable is just a name that holds a value, so you can reuse it instead of typing the value again and again.

Creating a variable

course="this is redhat course"

Important: there should be no spaces around the = sign — course = "..." will cause an error.

Using (printing) a variable

To use or print a variable's value, put a $ symbol in front of its name:

echo $course

This prints: this is redhat course

Making a variable permanent

Normally, a variable only exists for your current terminal session — once you close the terminal, it's gone. To make a variable available every time you open a new terminal, add it to your .bashrc file (found in your home directory).

Exporting a variable

By default, a variable you create is only available in your current shell. If you want other programs or sub-processes (like a script you run) to also be able to see and use that variable, you need to export it:

export name=ayyappa
echo $name

This will print: ayyappa

The export command turns a normal shell variable into an environment variable, meaning any process started from that shell can access it too.

Viewing Files: less vs more

Both commands let you view the contents of a file one screen at a time, instead of dumping the whole file on your terminal at once. But there are some differences:

Command	Behavior
more	Shows the file a page (screen) at a time, but you can only scroll forward
less	Shows the file a page at a time too, but you can scroll both forward and backward, and search through the file more easily

In both, you can press Space to move a full page forward, or Enter to move down one line at a time. The key advantage of less is the flexibility to go backward and jump around — which is why most people prefer less today, even though more came first.

What is .vimrc?

.vimrc is a configuration file for the Vim text editor. It lives in your home directory (~/.vimrc) and lets you customize how Vim behaves every time you open it — for example, automatically turning on line numbers, changing colors, setting tab spacing, or adding shortcuts — without needing to type those settings manually every single time.

Quick Recap

touch with brace expansion ({1..5}) lets you create many files in one command. Variables store values you can reuse with $variablename, and export makes a variable visible to other programs, not just your current shell. less and more both page through a file's contents, but less gives you more control by allowing backward scrolling and search. And .vimrc is where you save your personal Vim settings so they apply automatically every time you open the editor.