From Robert's Rules of Order:
Part I. Rules of Order; Article I. Introduction of Business; Section 2. Obtaining the Floor:
Before you can make a motion or address the assembly on any matter, you have to "obtain the floor." This means that you have to stand up (in a formal setting) and address the presiding officer (referred to as the "chair" in this book by his or her title, for example:
The chair will then recognize you by announcing your name or (if not known) by nodding in your direction:
The chair recognizes Ms. Davis.
But if the chair rises to speak before you obtain the floor, you must take your seat for the time being (see Section 36).
If you're conducting the meeting, it's up to you to recognize the member trying to get your attention. But what if two or more persons stand up at the same time? . . .
General H.M. Robert assembled the rules of Parliamentary practice in 1876, and they are still with us. Those who know Robert's Rules of Order have a huge advantage in steering organizations and boards toward conducting their business meetings effectively.
Likewise, members of Congress who learn every article and codicil of the Rules of the House and the Rules of the Senate (which differ from each other) have a similar advantage.
In Herding Cats: A Memoir of a Life in Politics, Trent Lott mentions many instances in which his total command of House and Senate procedures helped him win him political victories.