The cause of Cushing's syndrome boils down to: Your body is exposed to too much cortisol. There are a few ways that this over-exposure can happen, including taking certain medications and having a tumor on your pituitary gland or adrenal gland.
Difference between class and instance variables. Now, it should be clear what the difference between instance and class variables is. Class variables only have one copy that is shared by all the different objects of a class, whereas every object has itâs own personal copy of an instance variable. So, instance variables across different objects can have different values whereas class variables across different objects can have only one value.
First you must understand that classes are instances too -- instances of the Class class. Once you understand that, you can understand that a class can have instance variables associated with it just as a regular (read: non-class) object can. Note that an instance variable on Hello is completely unrelated to and distinct from an instance variable on an instance of Hello. A class variable on the other hand is a kind of combination of the above two, as it accessible on Hello itself and its instances, as well as on subclasses of Hello and their instances: