We started this chapter off by creating and running our very first shell script. As is almost mandatory when learning a new software language, we printed Hello World! onto our Terminal. Continuing, we explained the shebang: the first line of a script, it is an instruction to the Linux system about the interpreter it should use when running the script. For a Bash script, the convention is to have the file name end in .sh, with a shebang of #!/bin/bash.
We explained that there are multiple ways in which we can run a script. We can start with the interpreter and pass the script name as the argument (for example: bash hello-world.sh). In this case, the shebang is not needed because we're specifying the interpreter on the command line. However, normally, we run the file by setting the executable permission and calling it directly; in this case, the shebang is used to determine which interpreter to use. Because you cannot be sure about how a user will run your script, including a shebang...