How to make a globally available executable script in the scripting language of your choice

• Locate the path to the interpreter for the language you are writing in with the which command.

    which node
    which python
    which bash
    which ruby
  

• Add that path as an interpreter directive (using #!) on the first line of your script. For example if you want to write a node script and which node returned /usr/local/bin/node, the first line of your script should be:

    #! /usr/local/bin/node
  

• Write your script to do what you want.

• Give your script execute permissions for your user with chmod u+x <path_to_your_script>. For example if your script is called myScript.js and is located in your current directory:

    chmod u+x myScript.js
  

• Move your script to one of the directories in the path. You can discover which directories are in your path by typing echo $PATH into the command line, which will print a colon seperated list of each of the directories in your path. A common directory in the path for scripts you've written is /usr/local/bin/. You will probably need to use sudo to be able to move your file into that directory. If the script you've written has a file extension in its name, and/or some case, like camel case you'd rather modify, be sure to remove the extension and change the name of the script as you wish. Continuing with the example script called myScript.js:

    sudo mv myScript.js /usr/local/bin/my_script
  

• Alternatively, you can create a link to your script inside the path, without actually moving your script. ln <source_file_path> <destination_path> will accomplish this. Continuing with our same example:

    sudo ln mySript.js /usr/local/bin/my_script
  

• Use your script you're done. Tab completion will now work when you want to run your script, and which my_script will disclose its location. If you need to make edits just open the file in its new location and go to town.