What are the key differences between a thickness planer and a jointer, and how do these differences impact their respective functions in woodworking projects?

A thickness planer is used to make a board's thickness uniform, while a jointer is used to create a flat surface on one side of a board. The thickness planer is ideal for adjusting the thickness of boards, while the jointer is best for creating smooth and flat edges. These differences impact their functions in woodworking projects by allowing each tool to perform specific tasks that are essential for achieving precise and professional results.