The primary components of a bicycle are the wheels and the frame. The frame holds the wheels which are propelled by pedals. Also, the bicycle is steered using handlebars that are joined to the frame. Bicycles can be grouped into many categories. Classification of bicycles is based on their function, mode of propulsion, the number of cyclists, and even construction. Different classes of bicycles have been associated with different purposes. A bicycle will be used for a particular purpose if it meets the least number of characteristics required for that purpose. This paper highlights the classification of bicycles based on their functions. The first class encompasses mountain bicycles. Mountain bicycles are constructed to withstand a rough environment. They can handle obstacles that could be found on loose sand, grass, washouts, gravel, and even rocks. Mountain bicycles have many features that enable them to function properly. Some of them include; durable wheels, large gear ratios, knobby tires, tough brakes and suspensions on their frames and forks. This class of bicycles is commonly used in mountain biking, downhill mountain biking, and other tough bicycle races. The next classification encompasses hybrid bicycles. As the name suggests, these bicycles embrace one or more components of other bicycles. For instance, hybrid bicycles could integrate components of road bicycles or mountain bicycles. This characteristic makes hybrid bicycles be used for many purposes. Besides, they can be used in a wide range of terrains. Hybrid bicycles have been associated with comfort and user-friendly aspects. Therefore, they have become popular among all categories of people, including children and casual riders. The third classification encompasses racing or road bicycles. This class is associated with the least comfort. Instead of comfort being given priority, racing bicycles integrate aspects that enhance the speed. Besides, their handlebars are strategically positioned to enhance the aerodynamic posture of the cyclist. Racing bicycles are light and stiff, making it possible for the cyclist’s power to be transferred to their wheels. Equally, their gears have perfect ratios that enhance maximum pedaling. The fourth classification encompasses touring bicycles. Stability, comfort, and capability of carrying heavy loads are the key factors when touring bicycles are being constructed. Touring bicycles have numerous mounting points for luggage. Also, they have bottle cages where bottles can be stored. Additionally, their titanium frames enhance comfort. The fifth classification of bicycles is the utility bicycles that are designed for transport. Utility bicycles are the most common type of bicycles in developing countries. Also, they are the most common class of bicycles in the world. The introduction of this class of bicycles enhanced the use of bicycles for sports, recreation, and transport. The final classification encompasses cruiser bicycles. Some of the features of cruiser bicycles are the balloon tires and upright postures seats. Furthermore, these bicycles are straightforward. In most case, they are made of steel. Owing to their stability, they are commonly used by casual cyclists and riders. They could also be classified under the hybrid category because of their components. This class of bicycles was the most common in the United States between the 1930s and 1950s. Cruiser bicycles’ popularity enhanced their re-introduction in the 1990s. In summary, there are different categories or classes of bicycl