A cake is a firework that is constructed from many cardboard tubes glued together. Each tube normally contains a single shot, and these are all connected by an internal fuse. Once the cake is lit, the fuse burns from tube to tube, igniting each shot in turn. Thus, a 16 shot cake will have 16 tubes, a 49 shot cake will have 49 tubes and so on.

Cakes are designed to be set up on the ground. They remain on the ground but each shot is blown out of the tube and into the air above.

Cakes can contain an almost infinite variety of effects and timings. Some cakes are quiet, some are noisy. Some have effects that start as soon as they leave the tubes, others blow a shell high into the air where it bursts into life.

Many beginners do not understand the difference between "cakes" and "candles", and think that to get aerial effects they need to get a Roman Candle. In fact there is practically no difference between them; a cake is simply a number of candles fused together. This is why cakes are sometimes known by their more official title of "Roman Candle Combination".

Cakes normally offer the best value for money in your display because unlike rockets for example, which have one single effect, a cake will repeat its shots. So, a 16 shot cake will have 16 shots in sequence, one after the other.

Cakes come in many different shapes and sizes. Typical cakes contain 16, 25, 36 or 49 shots but it is not uncommon to see even larger numbers of shots. There is a legal limit on the weight of a cake (10Kg), so cakes with huge numbers of shots normally have lots of very small shots, rather than a few large ones. This is why cakes with 500 or more shots look like dustbin lids but each individual shot is tiny.

Generally, cakes with the maximum allowed bore size (the size of each tube, which dictates the size of the shot inside) of 30mm will have the most powerful effects. It is this bore size - not the number of shots - that determines how powerful each shot is.

Not surprisingly, cakes with large numbers of shots tend to last longer. A typical cake will last 20-40 seconds, anything longer than a minute is considered long in firework terms. Duration is also influenced by the internal fusing. Manufacturers can use slow burning fuse to make a cake last longer, or use fast burning fuse to create a more intense - but shorter - barrage. As you browse our reviews you'll see that the possibilities are endless.

Cakes start in price from just a few pounds, and some of the very large ones can cost £100+ Be aware though that very large cakes are often called "Single Ignition Boxes" or "Displays In a Box"; refer to the SIBS section for more information. Quality in cakes - like all fireworks - is not determined by price alone. There are some stunning cakes for around a fiver, and some equally naff ones costing ten times as much. Use our reviews to guide you.

One of the most exciting developments in recent years is the fan cake. Here, the tubes are angled slightly so that the shots are sent out to the left and right of the firework in addition to straight up. But even better, each row of shots is fused to fire simultaneously.

Fan cakes thus provide a stunning barrage of multiple shots. They tend to be expensive, but as you'll see from our on-line video the effect created is near-professional. They make ideal finale fireworks to end your show.

Where a fan cake fires its shots in a chaser sequence from left to right and vice versa, it is known as a "Z" firing cake.