In object-oriented programming, a property is an attribute of an object that holds data. The title of the book would be stored in a 'title' property of the 'Book' object. Methods perform actions or computations, not store data. Classes define the structure of an object but are a blueprint, not individual data points. A variable is a storage location paired with an associated symbolic name (an identifier), which contains some known or unknown quantity of information referred to as a value; while a property can be accessed with variables, the property itself contains the information you want to retrieve, in this case, the title of the book.