How to set a new environment variable?

To set a new environment variable in a Linux terminal, you can use the export command. Here’s how to do it:

1. Open your terminal.
2. Use the following syntax to set a new environment variable:

export VARIABLE_NAME="value"

For example, to set a variable named MY_VAR with the value HelloWorld, you would run:

export MY_VAR="HelloWorld"

3. To verify that the variable has been set, you can use:

echo $MY_VAR

This should output:

HelloWorld

Making it Persistent

If you want the environment variable to persist across terminal sessions, add the export command to your shell's configuration file (e.g., ~/.bashrc or ~/.zshrc):

1. Open the configuration file in a text editor:

nano ~/.zshrc  # for zsh users

2. Add the export command at the end of the file:

export MY_VAR="HelloWorld"

3. Save and exit the editor.
4. To apply the changes, run:

source ~/.zshrc

Now, MY_VAR will be available in future terminal sessions.