Cyclocross bikes look like road bikes at first glance, but they are built for riding off-road.
Cyclocross is a fast, furious and fun style of racing that involves riding these bikes on rough terrain, requiring some running, carrying, negotiating small hurdles and lots and lots of mud. Because of their comfortable and tough design, cyclocross bikes are often used for many purposes other than racing as they're very versatile. Cyclocross bikes are great for commuting, training, exploring off-road, touring and pretty much anything else.
Although cross bikes look a bit like road bikes, they have some special adaptations to make them suitable for off-road riding and racing.
Frame: Cyclocross bike frames are usually a bit more durable than road bikes and have clearance to take bigger tyres. They can be built from any material, but aluminium is common.
Gearing: Compact or cyclocross-specific chainsets give a wide range of gearing for frequent changes in gradient.
Cables: Cross bike usually have cables running along the top of the top tube rather than below it. This is to make it easier to throw the bike onto your shoulder and carry it.
Brakes: Cyclocross bikes used to have cantilever brakes to shed mud more easily, but disc brakes are now becoming common. Some cross bikes have extra mini brake levers on the top of the handlebars for panic braking on tricky terrain, called suicide levers.
Wheels & Tyres: Cross bikes have 700c wheels with durable rims. Tyres will be much fatter than road bikes, with tread to grip off-road.
Cyclocross bikes aren't just for cross racing. They're increasingly popular with all sorts of riders because their tough nature and comfort makes them incredibly practical.
Commuting: Cross bikes make great commuters. Many have eyelets for mudguards and a pannier rack and their relaxed geometry is great for riding in traffic. They're really durable as an everyday bike and you can fit narrower tyres to make them faster on the road.
Touring: If you can fit a luggage rack, a cross bike makes a great touring machine, especially if you want to go off the beaten track.
Sportives: Cross bikes are often very comfortable so they're a wise option for sportives and other long rides. They might not be quite as nippy as a road bike though.
Everything Else: If you're not quite sure if you'd rather have a road bike, a mountain bike or a hybrid, a cross bike might be the bike for you. They combine attributes from all these categories, so if you're not sure what type of cyclist you are, a cross bike lets you try out lots of different types of riding.