Robert's Rules of Order are a very popular set of rules for running meetings. If you've been at a meeting run by a chairperson that had moving, seconding, motions, and majority-rule votes, it's quite likely that meeting was run by Robert's Rules or a modified/simplified version of Robert's Rules.

If your non-profit's bylaws use the word “may” rather than “shall”, then your non-profit has more discretion on how to run the meeting. Most non-profits do not need to follow Robert’s Rules to have a productive meeting.