These are found around the side wall of a tyre...
Max and Min. pressure is marked in Bar and Pounds per Square Inch (PSI).----> The harder the tyre, the easier the ride. |  | The 'Drive' marking is very easy to overlook ------------> Mount the tyre on the rim to rotate as indicated when ridden. |  | Yes - size IS important! Tyre size marked in Imperial - this one is 28 inches diameter, 1.1inch wide---> Can also be marked in Continental system eg. 700x28C |  |
POPULAR TYPES OF BIKE...
Mountain, touring, racing, hybrid, probably a few more. A brief look at each;
The Mountain
Probably the most common seen around, and the most widely sold. Maybe because those chunky tyres look unlikely to puncture, so great for all that fun off-road stuff and our leisure trips up the canal. BUT - can be harder and more noisy to pedal on tarmac - which is where we want to encourage you to be!
Some mountain frames - and saddles - are 'sprung' or have 'shock absorbers'. Great (essential) on a car, maybe not so on a bicycle - can absorb that valuable pedalling power.
Very wide range of gears - maybe three 'chainrings' (at the pedal cranks) and several (typically five or more - called the block) on the rear hub. Choose a cycle with as many rings and block gears as you can afford with a wide ratio ( difference between smallest and largest). On the rear - the gears you will be changing most often - the small ones give speed, the larger are selected when climbing. As you get better, and fitter, you WILL want to go faster, and climb hillier!
And please (you will thank me eventually) have mudguards fitted! Many mountain machines are sold without m/guards, either to keep cost or 'weight' down (!) The first bit of mud you go through, there's a streak of dirt right up the back of your clothing! Don't buy without, thinking you will add them later - you won't!
The Tourer
A lighter frame, more narrow tyres with a finer tread, usually 'dropped' handlebars. Much better (quieter, smoother, less 'rolling resistance') for on-road cycling and for any longer journeys. Again, go for as many gears as you can afford. Ratios CAN be changed but you WILL want more than you started with if the cycle only comes with few gears.
The Racer
Similar in appearance to the tourer but even lighter frame, slimmer tyres still (for even less rolling resistance). Tend to have much closer block ratios to keep a steady pedalling rhythm at different speeds so maybe less suited where speed is going to change significantly. Used extensively for very long distance riding, time trials etc.
The Hybrid
A design between the mountain and tourer. A sturdy frame, tyres with an obvious but not 'tractor' tread, wide gears, to give a reasonable ride on-road and extra toughness off-road. Some cyclists have a mountain and a tourer. Much depends on how much cycling you THINK you will be doing, and where the majority of this might be.