The main function of the tread pattern on tyre is that

• the tread grooves pass air between the tyre and road surface, thereby preventing tyre from overheating
• the crests between the tread grooves absorb road noise
• in wet conditions, the tread grooves expel water that is drawn between the tyre and road surface
• the tread pattern protects the tyre's inner carcass from small stones and pieces of glass