Shebang

A shebang is used to tell the Operating System what kind of Interpreter should be used to run the script.

it is placed at the first line of a script file, whether it may be a Node .js, Python .py, or Bash .sh file.

#!/usr/bin/bash
echo "I'm being ran with bash!"

# this only works on Unix-based systems
./index.js
# we have to use the node command in Windows
node index

Finding the Proper Shebang Directory

With the Bash which command, we can find the location of any executable.

$ which bash && which node && which python
/usr/bin/bash
/c/Program Files/nodejs/node
/c/Users/LENOVO/AppData/Local/Programs/Python/Python310/python

#!/c/Users/LENOVO/AppData/Local/Programs/Python/Python310/python
print("I'm being ran from Python!");

/* index.js */
#!/usr/bin/env node
console.log("I'm being ran with Node.js!");