Bike pumps are used to inflate tyres. They are available in three main styles which are floor pumps, hand pumps and C02 cartridges. Floor pumps are the most effective pumps. They are large, generally have a pressure gauge and are capable of high pressure inflation (up to 200psi). Hand pumps range in size and effectiveness. Generally attached to the bike incase of a flat tyre on the road or trail. Due to there size the inflation levels are not as high. C02 cartridges are very handy for when you need to quickly pump up and go. Very small in size, one use only, they pump your tyre to about 100psi.