How to set global variables from within a script

Question

Is this possible? I want to change and or create global variables in a bash script.

Karim Maassen · Answer

I want the variable to be changed by a script. Not manually.

Jobin Kuruvilla [Adaptavist] · Answer

Why don't you create a plan variable and change it if you need to do that later.

Karim Maassen · Answer

I see how I can use global variables. But, they aren't really variables, are they? I can't change a set global variable once it's been defined. Or am I mistaken?