A manner is the way something is done or the way someone behaves. When your teacher asks you to solve a math problem in a certain manner, she's asking about your method or approach. When someone completes a task in a professional manner, they do it carefully and competently.

The word often describes how people act around others. Someone with good manners knows how to be polite and considerate: they say please and thank you, wait their turn to speak, and treat others with respect. Poor manners might mean interrupting, being rude, or ignoring social expectations. Manners are ways of showing respect and helping others feel comfortable.

You'll also hear manner used to describe someone's general way of being. A person might have a cheerful manner, meaning they seem upbeat and friendly. A stern teacher might have a serious manner that keeps the classroom focused. Your doctor might have a calm, reassuring manner that helps nervous patients feel better.

The phrase “all manner of” means many different types: “The library contains all manner of books” means it has many different kinds. When something happens “in this manner,” it happens in this particular way.