In this post, you will learn how creating a script in bash as well as how to edit your PATH to allow you to run in from anywhere. Specifically you will:

  • Learn about Evironment Variables
  • Learn how to change your $PATH to run scripts anywhere
  • Learn what is a .bashrc / .zshrc file
  • Learn about aliases


  • Have read through my series on the basics of bash or have a general understanding of how to move around edit files in bash

Environment Variables

Environment Variables are a special type of variable that are always accessible. They are available in every script on your computer and can even be used from the command line. One example is the HOME, which is your home folder:

echo $HOME  #  👉️ /home/buddy/  # Note, yours will be different

To set an environment variable you can use the export command. For example, you can set your name as an environment variable with the following command:

export NAME="Your Coding Buddy"

Now you can access this variable from the command line with:

echo $NAME  #  👉️ "Your Coding Buddy"

You can see a list of all of your environment variables with the env command. I have a lot of environment variables, so I won’t show my output, but there is one in particular that you should note. That is the $PATH variable.

What is the $PATH variable and how to we adjust it

The PATH environmnet variable is a special one. This variable tells your computer where to look for terminal commands. So your computer will look at each folder to find the command you try to use. If it does not find the command in that folder it will continue to the next until it finishes the full PATH.

Note: Do not confusion PATH or $PATH with path or path/to/dir. Typically, the latter two refer to the location on your filesystem where the former to are the actual environment variable.

By default your path is:


Each of the colons :, signifies a different directory. So when looking for a command it will first search in /usr/bin then move to /bin if that is unsuccessful and so forth.

It is very common practice to edit your PATH to allow you to have access to other commands regardless of what directory you are in. Here is my PATH:

My Path

Just like you saw previously, you can use the export command to change your PATH since it is an environment variable. For example, you can add the first_folder to the beginning of the PATH with:

export PATH="$HOME/Documents/first_folder/:$PATH"

Remember bash is case sensitive, so make sure you type in the correct directory location.

This command will adjust your PATH to include the first_folder at the beginning of your PATH before it searches any other folder. Note I use the HOME environment variable so I don’t have to type out /home/buddy, then after the folder name I use a : to separate the next folder in the sequence. Then I add the PATH variable again at the end. This allows you to keep the old PATH at the end without removing it. It would mess up your whole system if you were to accidently remove the old folders from your PATH. In case you ever do mess up your path you can always use this to reset it. Here I don’t include the PATH variable because I am resetting it entirely.

export PATH="/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin"

One thing you will probably notice, is that anything you export only lasts as long as you have the terminal open. If you close it, everything resets. To solve this, you can adjust your .bashrc or .zshrc to make them permanant.

What is the .bashrc/.zshrc and Why do I Need to Know it

When assigning an environmental variable with export, it will only last for that session. If you open a new tab/window or if you close this one and open a new one, you will not longer have access to that environment variable. This is where .bashrc and .zshrc come into play. These files are run everytime you open up a new terminal, so if you add the export command to your rc file, it will be available everytime you open up a new terminal/tab.

Its important you know what shell you are using to know which file you need to edit because you might have both. To check you default shell you use, you can run either of the following commands:

echo $0
echo $SHELL

Once you know which shell you are using, you will need to find the file. They are both located in your home directory, so for bash its located at ~/.bashrc. The zsh one is located at ~/.zshrc. Note the . since these are hidden files. Add the relevant export to the end of this file (you learned about appending with echo or edited with your favorite text editor).


Perhaps the most valuable rc changes you can make are your aliases. aliases are alternative shorthands for command. You can assign an alias to any command. Some common examples include aliasing the ls -lha to ll. The general structure of an alias is:


so for the example above you would do

alias ll="ls -lha"

now, instead of typing out ls -lha, you can just type ll to get the same output. Here is a list of a few common aliases, but you should try to make your own, just don’t forget to add them to your bashrc or zshrc file or you won’t have permanant access to them.

  • ll="ls -lha"
  • ..="cd .."
  • ...="cd ../..": I have this repeated a few time so I can go back many directories just with .....
  • g=git: Notice, you don’t need quotes if you do not have any spaces in your command
  • ga="git add"
  • gcm="git commit -m"
  • myip="curl": Prints your public ip address

For more common ones, you can check out this repo.


In this post, you learned about bash environmnet variables and how to update your PATH to run scripts from anywhere. Finally, you learned about making changes to your environment permenant with ~/.bashrc or ~/.zshrc as well as how to add aliases to the .rc file.