We need to take a small step back and discuss some terminology—parameters and arguments. It's not terribly complicated, but it can be a bit confusing, and they are sometimes used incorrectly.

Basically, an argument is something you pass to a script. What you define in the script is considered the parameter. Look at the following example to see how this works:

reader@ubuntu:~/scripts/chapter_08$ vim arguments-parameters.sh
reader@ubuntu:~/scripts/chapter_08$ cat arguments-parameters.sh 
#!/bin/bash

#####################################
# Author: Sebastiaan Tammer
# Version: v1.0.0
# Date: 2018-09-08
# Description: Explaining the difference between argument and parameter.
# Usage: ./arguments-parameters.sh <argument1> <argument2>
#####################################

parameter_1=${1}
parameter_2=${2}

# Print the passed arguments:
echo "This is the first parameter, passed as an argument: ${parameter_1}"
echo "This is the second parameter, also passed as an argument: ${parameter_2}"

reader@ubuntu:~/scripts/chapter_08$ bash arguments-parameters.sh 'first-arg' 'second-argument'
This is the first parameter, passed as an argument: first-arg
This is the second parameter, also passed as an argument: second-argument

Variables we use in this manner are called parameters inside the scripts, but are referred to as arguments when passing them to the script. In our name-improved.sh script, the parameter is the name variable. This is static and bound to the script version. The argument, however, is different each time the script is run: it can be Sebastiaan, or Sanne, or any other name.