Debate is the heart of any decision making process. But uncontrolled debate is useless, in fact, counterproductive. The basis of Roberts Rules is to create an orderly system of debate and action. Therefore there are specific rules governing debate.
1. Only one person may speak at a time.
This is done by the person(s) who wish to speak rising (or raising hands) and being recognized (called on) by the chairman.
2. Time is limited.
Unless your own rules stat otherwise any person may only speak twice, for ten minutes each time, on any motion, on the same day. If a motion is carried over to a different meeting or day, the persons right to speak starts over. Please note: the Filibuster is unique to the US Congress, and is not allowed anywhere else. And, unless you have a specific rule to allow it, a speaker cannot yield time to another person.
3. One person cannot dominate the debate.
Each person may only speak once until everyone who wishes to speak has done so, then someone may speak a second time. In order to speak a third time on the same matter, the speaker must have permission of the entire assembly. (majority vote allows a third speech)
4. The rules of debate require a 2/3 vote to change.
Because changing the rules alters the rights of members, a 2/3 vote is required to change the rules of debate, or to adopt special rules of debate if you have none currently.
5. Speakers must stick to the topic.
All remarks must be Germane, that is, pertain to the question at hand. If you are debating an amendment, the debate is limited to the amendment, and debate on the original motion is not in order, likewise if a motion has been made to refer the matter to a committee, the debate is limited to the merits of the referral, debate on the motion itself is out of order.
6. Speakers must be polite.
Speakers should not attack the motives of other speakers, or question their integrity. Neither should speakers yell, use foul language, or make remarks that are personal in nature about another person or speaker. The debate is on the merits of the motion, not the other members.