In algebra, we learn about functions of various types. these functions are often seen in a progression from least complicated (linear) to most complicated (piecewise with nonlinear parts). and then there are other types of functions in-between: exponential, quadratic, polynomial, radical, and logarithmic. but with all their differences and unique properties, these share a common trait of being functions that we can graph in a coordinate plane. what are some other things you can observe to have that same quality of functions: unique, but sharing a common trait or purpose?