Having good manners and knowing what the rules of etiquette are will make you more comfortable in all situations of everyday life both personally and professionally - it makes no difference where you are - you will always be at ease because you are confident in your own being. You won't need to spend time worrying about your own presentation. Rather, you can afford to take the time to make others around you feel comfortable. Every occasion is more enjoyable when everyone is comfortable.
Possessing good manners means you possess a certain "kindness of spirit" - a je ne sais quoi - that enables you to be considerate of other people, charm them, and make them feel welcome around you.
Etiquette, on the other hand, serves as a roadmap of civilized society and allows us to showcase that kindness of spirit, graciousness, and good manners. Knowing the rules of etiquette and having a certain savoir vivre - knowledge of the ways of polite society- greatly reduces the likelihood for confusion and encourages opportunities for cordiality. Taken together, these qualities allow you to shine both personally and professionally. Pure and simple.
