Nothing wrong with your understanding. Of course - contents may vary depending on location and plans.
In a nutshell - BOB (bug out bag) is something you can grab quickly to leave your current location (mine are staged in a closet near the door). Their use is generally considered for short term use (a few hours to a few days).
A GHB (get home bag) is just as it sounds - something to get you back home from wherever you have traveled (work, shopping, etc). Again, their contents will vary depending on geography, distance, etc.
For me - since my concerns for bugging out are weather related, man made (things like train derailments, meth lab, terrorist attack, etc) my BOB also includes copies of insurance paperwork, photos of property, important phone numbers etc.
I believe the most important thing one can do when making up a BOB or GHB is to make a list of possible reasons it might be needed (threat assessment) and then prioritize that list. It is also important to be realistic and not rely too heavily on the latest movie or novel to prioritize. While both may give some great ideas and food for thought, living in the "real world" is what is important.
The concerns of living in a jungle environment, remote forest location, urban setting or above the arctic circle will dictate what our threats are and we should plan accordingly.