In science, models are systems used to stand in for real-world systems of interest, or target systems. Models are especially useful when it’s impossible to experiment on the real-world target system, either because it’s too large (like the sun), or it’s too remote (like other planets), or it no longer exists (like dinosaurs), or there would be ethical concerns (like testing some new drugs). This video explores the variety of types of models used in scientific research, and how different kinds of models are similar in different ways to the target systems they are used to investigate. This video is aligned with Chapter 5 of the book Recipes for Science: An Introduction to Scientific Methods and Reasoning, by Angela Potochnik, Matteo Colombo, and Cory Wright.