[Ale-study] Questions from Last Meeting

[DJ-Pfulio]

What are the differences between
* useradd -g users bob
* usermod -g users bob
* usermod -Ga users bob
* usermod -G users bob
* useradd -G users bob
* gpasswd -a bob users
* gpasswd -A bob users
* gpasswd -M bob users
When would each produce unexpected results?
Suggestion: play with some different groups.

Please don't answer until Thursday to let others have a chance.