Functions, including first-class, review demo
	- Plotting functions with the turtle!
	- Functions with composition of multiple sines
	- "harsh" audio distortion with transistors

Class: A definition of a collection of objects and data
Object: An instance of a class
Instance:  An example of a definition of something
	- Car example
	- In the car example, classes might be expensive
Method: A function that is part of a class
Property: A variable that is part of a class

These are a way of organizing data and functions together
Maintains state without global variables
There are objects in the standard library
	- Files
	- Strings
	- Lists

A couple more terms:
	- Constructor
	- Destructor

Compare and contrast with Java classes:
	Java expects you to love objects
	Java:  Everything is organized in classes
		- Want a simple program?  Use a class
		- Want a library?  Use a class
		- Want a function?  Put it in a class, and call it a method
		- Want a bunch of constants?  Put them in a class as static properties
		- Want a global variable?  Use a class-level static variable instead
		- Some of these can be hacked around, but we're going with the flow here
	Python:  Classes underly everything
		- They're like the floor.  You can interact with it, or just walk on it.
		- Python itself is built object-oriented
	Let's think about what is presented to the user!
		- How many of you have semi-metallic brake pads on your car?
		- vs. organic or ceramic
	Was Java written by heartless object proponents?
		- Do they attach eating to the cat or the food?
	Java is designed for graphical application programming!
		- GUI is usually a collection of objects!
		- If you're going to program with OO, might as well embrace it!
		- ffui
		- Don't play salmon

We can make classes that represent things
	- Like a square
	- methods:  area, perimeter, draw

Ok, how about a collection?
	With super bonus iterators!