Shot glasses can come in all shapes, designs, sizes, colours and content capacities. The UK Weights and Measure standard dictates each shot glass must contain either 25ml or 35ml of liquid for official public use.
The original shot glasses or "whiskey Taster" as they were known, can be traced back to the American Wild West. Each glass was hand-blown with a thick base. As time marched on, manufacturing techniques changed and glass moulds appeared with the glasses becoming much thinner and with smaller bases.
It is not exactly known when the term 'Shot' came into being or into common usage. It is thought to date back to the 1930-1940's. Up until this point, the word 'Jigger' was used. Professional Mixologists however still use Jiggers to measure their alcohol and mixers. Instead of being glass, Jiggers tend to be made of metal. Glass shot glasses because of their legal requirements can and are used as measures in many bars and Cocktail lounges.