• London Dry Gin
London Dry gin is the most common type of gin and is considered by many distillers to be the most sophisticated type of gin. Despite the name, it doesn't have to be produced in London to be considered a London Dry Gin. The term actually refers to the specific type of production process. This process of gin distilling has to meet the legal definition to be able to call itself London Dry. This gin variant has less than .1 gram per litre, which gives it its dry taste, has no colour and has to be predominantly juniper flavoured.
• Plymouth Gin
Another English Gin, Plymouth has a slightly sweeter taste than London Dry gin. Plymouth gin has a more subtle juniper flavour with emphasis being placed on the root botanicals like licorice and orris. Unlike the London Dry Gin, this style MUST BE MADE IN PLYMOUTH.
• Old Tom Gin
Also known as a "bathtub gin" (because it was made in residential homes during the 18th century), this gin variant is much sweeter than both Plymouth and London Dry. Old Tom is the "missing link" between dry, modern styles of gin and Genever. It is the simply syrup in this variant that distinguishes this style from the contemporaries and includes notes of citrus, but this isn't the case for all Old Toms, which is what can make it confusing as to what makes the gin an Old Tom.
• Sloe Gin
Technically speaking, Sloe gin is a British red liqueur made with gin and sloe berries (a red fruit closely related to the plum). While the sloe berry is very sour in taste, it actually makes for a rich, sweet and tarte gin. Sloe gin has less alcohol than a regular gin and is the perfect winter warmer if you want to have a cheeky drink in the colder months.
• Navy Strength Gin
The namesake of this variant pretty much translates to London dry that's overproof. Navy Strength also originates from when gin used to be stored below deck with the gun powder. If the gin was spilt onto the gun powder and it produced smoke it would mean that the gin was diluted, but if the gun powder lit, the gin was at least 144 proof (57% ABV) and so became Navy Strength. The easiest way to explain this varietal of gin is to think of it as a London Dry on steroids that'll put hairs on your chest.
• Contemporary Gin
This style gin has a predominant flavour of anything other than juniper. While it is somewhat present, the overall gin has a bit of character that emphasizes the other botanicals.
• Barrel-Aged Gin
Barrel-aged gin is a relatively new invention as they were a product of the 00s-10s gin renaissance. Today's aged gins use wine barrels, bourbon barrels, rye barrels, you name it! Barrel aging a gin gives it many classic aged spirit flavours that you wouldn't normally associate with gin such as vanilla, oak, caramel, and smoke.
• Genever
While this one is rarely considered a gin, it is sort of though as a grandfather to today's gin. Genever is just the spirit drink from where gin began.