Barbel (Barbus barbus)
A powerful and hard fighting fish, naturally found in fast flowing water.  Beautiful, long and sleek but muscular, with a downturned large mouth and barbules around the mouth giving it it's name.
Likes big meaty baits like luncheon meat, big pellets, pepperoni but will also occasionally take boilies, maggots or worms. Very shy fish so bait presentation is important. A longer than usual hook length can help, as can a minimal set up. I often use meat with no feeder or lead, depending on the conditions.
Specimen fish can reach high teens in weight.
Recommended mainline: 8lb

Chub (Leuciscus cephalus)
A common fish in British rivers and canals. Likes some flow and cover of overhanging trees and so on.
Will happiliy take maggots, bread, pastes, worms, pellets. My personal favourite being cheese paste. Can put up a hell of a fight when fully grown.  Similar scaling to common carp, large mouth, muscular and lean.
Specimens can reach 6lbs plus.
Recommended mainline: 4-6lb

Common Carp (Cyprinus carpio)
One of the most popular of British fish, found in all types of water but mostly stillwaters with many fisheries made especially for them. Originally imported and farmed by monks for food, carp have become the target species of many anglers with specimen fish going way over 30lbs in weight. Methods are many and varied for all large species carp, from method feeders with boilies, to pop up pellets, floating baits and even fly fishing!
Large mouthed fish that can feed voraciously and even have powerful teeth at the back of the throat to chew up harder foods!
Recommended mainline: 6-8lb for smaller fish to 10lb ish
15lb for specimen

Mirror Carp
As common carp but large scales intermittently spaced.

Crucian Carp (Carassius carassius)
Perhaps the least often caught of the carp these days, the crucian is smaller and deeper bodied. Once prolific in our waterways, they are now few and far between making them a joy to catch when one does get landed. Hard fighters, like most baits associated with carp but more partial to maggot and worm than the big fellas.  Can grow to 5lb+
Recommended mainline: 4-6lb

Tench (Tinca Tinca)
A beautiful olive green fish with red eyes. Can get into double figures and are one of my personal favourites. Slimy to the extent of a bar of soap! Hard fighting - pound for pound, one of the hardest. Love maggots, particularly red, worms, sweetcorn. Will also take pellets and bread baits.
Known as the "doctor fish" due to apparently antiseptic qualities of it's slime. It is believed injured fish will seek them out to rub against them.
Recommended mainline: 6lb

Common Bream (Abramis brama)
Relatively slender and deep bodied gaining the nickname "slabs" . Very slimy fish and not the hardest fighters, but they do tend to move around in groups so one fish usually leads to more and huge bags of bream can be caught in the right conditions. Live in both running and still waters.
Often succesfully caught using a feeder with a light quiver or even a swing tip. Prefers ripple of wind on the surface and will readily take maggots, sweetcorn, bread based baits, worms, pellets.
Recommended mainline: 4-5lb

Pike (Esox lucius)
A fierce British predatory fish. Incredibly fast and agile moving from a standstill to grab passing fish in a flash!
Very saught after, once routinely killed in the belief they were pests, now only culled if population is proved to be harming the balance of the waterlife.
Usually fished with deadbaits or imitation fish like shads, spinners or plugs.  Can reach big weights but fairly common in sizes upto a few pounds. Smaller fish are known as "jack pike"

Zander
The "Zed" is a fiecre British predator that should be fished for as you would pike. More commonly occur in Eastern England with Norfolk area being particularly good hunting ground.
Often mistakenly called the "pike-perch" the zander is in fact a species in it's own right and not related to either!

Dace (Leuciscus, leuciscus)
Possibly the smallest fish I ever saw! Small enough to make me wonder what it was but I believe a Dace due to the dark back and upturned mouth. Prolific in our rivers, these are usually caught in ounces rather than pounds.

Roach (Rutlius rutilus)
Without doubt, one of the most common of British fish, this is often the first fish a youngster will catch. That said, they are beautiful fish and can be caught in vast quantities in the right conditions. Popular methods are maggots, pinkies, casters, hemp, breadpunch fished from a whip or pole so as not to disturb the shoal too much. Slight bites make sensitive tackle essential but they do still come out to rod and reel anglers all the time.
Most commonly below a pound, but specimens can be 3lb+
Recommended mainline: 2.5lb with a lighter hook length

Rudd (Scardinius erythrophthalmus)
A lovely fish that has become fairly scarce in recent years. A lot like a roach with similar feeding habits. Lovely golden colour and similar in size to roach.
Ide/Orfe (Leuciscus cephalus)
Ide have become more common in recent years and tend to reproduce rapidly. They often confuse anglers and are mistaken for a hybrid but are a species related to carp. I describe them as a non-slimy roach that is shaped like a chub.
Often found in large shoals and can produce excellent sport, particularly up in the water or surface fishing. Will take bread punch, maggots, casters, pellets greedily.
Restrictions are now in place for stocking these in fisheries as there have been problems with them taking over completely.
Non-the-less, good sport with heavy bags of fish over a pound commonplace.
Recommended mainline: 3lb with a slightly lighter hook length
Gudgeon (Gobio gobio)
A small but very common fish. Prevalent in our rivers and canals, they look very similar to a tiny barbel.
Can be fun but also difficult to avoid at times as they are so happy to feed on maggots!
Set up light if you want to fish for these as it is rare for gudgeon to be more than a few ounces.
Ruffe (Gymnocephalus lavaretus)
Another of our waterways' small species, but less common. The ruffe has a dorsal fin similar to a perch but does not become a large fish like a perch can. The one pictured is a good size!
Another one that loves the maggots!
Set up light
Perch (Perca fluviatilis)
This fish along with roach are the most commonly caught in Britain. The perch is actually a predator and bigger specimens can reach a few pounds and be hellish to land. More common are the smaller ones that kids can catch all day on maggots!
Set up light for small fish to a pound but treat as small pike and spin or use deadbaits or worm for larger fish. The bigger fish respond particularly well to feeding chopped worms.  A 3lb+ fish is a real achievement as they become very shy with size.

Grayling (Thymallus thymallus)
A truly beautiful creature this, the grayling is known as "The Lady Of The River". Serene appearance, with a very long dorsal fin like a sail. This is a rareity in that it is one of the few crossover species that are fished for by both game and coarse fishermen. Hard bony mouth parts mean unhooking can be difficult and indeed, keeping a hook in them can be too!

Brown Trout (Salmo trutta)
The common quarry of the fly fisherman, but sometimes will take a maggot and confuse novice coarse anglers!
Related to the salmon, this is very good eating and doesn't really want to be landed at all! Fights harder than most! Known as "brownies" or "spotties"

Rainbow Trout (Salmo gairdneri)
More like it's cousin the salmon than the brown trout. Grows larger, fights harder, looks nicer with its stunning colouration. Fly fisherman's favourite!