Let's define instance variables (ivars):
Ivars are the data or properties on a class.
Examples:
- The ivar firstName in a Person class
- The ivars width and height in a Rectangle class
- The ivars name, weight, and favoriteFood in a Dog class
Note that the number of ivars will vary depending on the problem statement. For example, we have a very simple model of a Person class (one ivar). However, for a more detailed problem, a Person class could have many more ivars (e.g., lastName, address, contactInfo, etc).