Knowing how conditionals work in bash open up a world of scripting possibilities. We’ll learn the basic syntax, including
elif. Then we'll look at a few of the "primary" operators you can leverage in a conditional statement such as
= for string equality,
-eq for numeric equality, and
-e to check if a file exists. After that, we'll use conditional statements to create a function that asserts that the HTTP status of a given URL is between 200 and 299.
This may help others: https://stackoverflow.com/questions/18928260/if-command-with-user-input-osx-terminal