According to the BASH Reference Manual:
export [-fn] [-p] [name[=value]] Mark each name to be passed to child processes in the environment.
An example I've come across:
PS1=<\u\h \W>\$ export PS1
What I've gleaned from the documentation, and examples, is that export is used to permeate a change in the environment across multiple shells? My confusion comes form the numerous times I have not seen it used in similar circumstances, yet everything remains working as intended.
E.g, I created an environment variable to track the load order of my profile files. Here is an example from my .bashrc file:
and it produces this behavior
$ echo $PROFILE_ORDER /etc/bash.bashrc:~/.bashrc
If my understanding of export is correct, then why didn't I need to use it in creating and modifying $PROFILE_ORDER?