Locomotive wheel arrangements refer to the configuration of wheels on a steam or diesel locomotive. These arrangements are often denoted using a notation system, such as the Whyte notation, which categorizes wheels by their number of leading, driving, and trailing wheels. For example, a 4-8-4 arrangement has four leading wheels, eight driving wheels, and four trailing wheels. Different wheel arrangements affect a locomotive's performance, stability, and speed. Common arrangements include 2-8-2, known as the "Mikado," and 4-6-2, known as the "Pacific." Each configuration is designed for specific tasks, such as freight or passenger service, optimizing the locomotive's efficiency and handling.