A toaster a.k.a. a toast maker, is a small electric appliance designed to brown or "sing[e]" sliced bread by exposing it to radiant heat, thus converting it into toast. Toasters can toast multiple types of sliced bread products. Invented in Scotland in 1893, it was developed over the years, with the introduction of an automatic mechanism to stop the toasting and pop the slices up–the "pop up toaster" in 1919 being a significant development. The most common household toasting appliances in the 2010s are the pop-up toaster and the toaster oven. Bread slices are inserted into slots in the top of a pop-up toaster, which make toast from bread in one to three minutes by using electric heating elements. Toasters have a control to adjust how much the appliance toasts the bread. Since the 2000s, pop-up toasters with wider slots have been manufactured, enabling them to toast bagels cut in half or thick-sliced "Texas toast". Another trend of the 2000s is the increasing availability of four-slice toasters.