The steering system knows how to turn the car. You know how to drive the car, eat lunch, write manuals, etc. We also learned that objects interact. They do this by sending messages to each other, which invokes a method. The sending object uses a message to ask the receiving object to use one of its methods to perform a task that the sending object cannot do.
Messages mimic the way things in the real world communicate.
The engine uses a method to go faster. Like real-world items, objects fit into different groups, called classes. Classes assist object orientation to achieve its streamlined functioning by defining things common to all objects of a particular sort. This means that the code necessary to define common object information must only be written once to forever apply to any object that is now or will be in that class. Object know what class they belong to, and can act on that knowledge, since the methods they use to act are stored with the class.