In JavaScript, dot notation is a way to access the properties of an object. For example, if you have an object called person with a property called name, you would access the name property using person.name.
You can also use dot notation to call methods on an object. For example, if you have an object called calculator with a method called add, you would call the add method using calculator.add().
Dot notation is a very convenient way to access the properties and methods of objects. It is also very easy to read and understand.