Car generations are lifecycles of design for a specific model car, while facelifts are refreshes or tweaks made to an existing generation. When automakers adjust the way the car looks, upgrade materials used, or even improve some of the features to keep up with the latest trends and advances, this is called a facelift. When the vehicle gets fully redesigned, and changes are more than just skin deep, it becomes a new generation. CarBuzz’s guide to buying a used car details all facelifts and highlights the differences between various generations.