Rum History / Styles

Rum has its origins in and around the Caribbean and its history is tied to sugar, colonialism and slavery. Originally produced as a way of extracting some use from the waste material from sugar cane - molasses - rum is made using techniques familiar to the whisky enthusiast... adding yeast to the sugary wort (or molasses) to trigger fermentation, distillation in either pot or coffey stills, then maturation in casks. The story is even more varied than that of Scotch Whisky production, however. 

As a guide, here are some of the basic styles of rum, in rough order of style from lighter to heavy: 
Cuban/Latin Style: Light and delicate, with admirable finesse. Bacardi now dominates the world, and is a famous example of this lighter style, made using continuous stills. 
Rhum Agricole - Produced on the French Carribbean islands, this type of rum is made using fresh sugar cane juice rather than molasses as its starting point. This produces a more vegetal sweetness, without so much of the heavy treacly sweetness of other rums. It is often matured in spicy French oak casks too, and is often said to have a more cognacy, "grippy" palate. Good examples: Barbancourt and Clement.
Demerara: A "soft, subtle, medium bodied style" says Dave Broom, although this can depend on the specific still. A lot of the 'dark' rums such as OVD etc called themselves Demerara rums because they had Guyanese spirit as their base. However, the huge amounts of caramel added to these blends masked any true Demerara character. All Demerara rum comes from Guyana, on the North-East tip of South America, and where 200 distilleries used to operate, only one now does: Diamond Distillery. This contains a cornucopia of stills however, with wooden pot stills, Coffey stills, copper pot stills, and the last working wooden Coffey still in world (named Enmore). Crazy! 
Barbados: The Bajan style is gorgeously soft, balanced and easy-drinking. Perfect for someone who likes something "smooth" for easy-slugging. Good examples: Doorly's XO and Mountgay Extra Old. 
Jamaica: In the same way as Islay whiskies stick out a peat-lashed tongue at the lighted, rounded style of other malts, Jamaican rums are defiantly individual. Distilled in pot stills with loony levels of esters, their pungency can take a little getting used to, but behind this are lots of ripe bananas and pineapple notes. Also referred to as the Wedderburn style.