A Hamburger is a simple sandwich usually made of grilled hamburger meat served in a bun. Hamburgers are the result of true American ingenuity: Steal a foreign idea and commence mass production.
Ground meat has fed people for thousands of years, therefore the Hamburger's specific origins are difficult to distinguish. The Hamburger as we know it has only been around for a hundred years or so. Hamburgers are said to have evolved from the Hamburg Steak. Although the Hamburg steak was a salty, smoked slab of minced beef made to survive long sea journeys, it quickly gained favor with the lower masses. Restaurants soon added fresh meat and the Hamburger emerged.
Artist's conception, late 1800's.
Hamburgers aren't just an American food anymore. Over the years, the popular sandwich has traveled to all corners of the Earth, taking on characteristics of each different region. For example, Aussies often serve theirs with a fried egg and a slice of beetroot in the mix.
Along with that sweet sweet koala meat.
Hawaiians often add pineapple slices and teriyaki sauce. A Pakistani hamburger is made of minced lamb with lentils and served with scrambled egg and ketchup. Indian hamburgers substitute chicken in place of beef, seeing as how slaughtering cows would be like slaughtering angels for their flesh.