A pedalboard is a keyboard similar to a piano keyboard that is played with the feet instead of the hands. Originally developed in the middle ages for playing the lowest notes on pipe organs, their range of applications expanded during the twentieth century to include theater organs and electronic organs and subsequently from the 1970s to include standalone pedalboard synthesizers and in the 1990s to include MIDI pedalboards. In addition to being located at a lower level than conventional keyboards for convenient manipulation by the feet, such as at the base of the console of pipe organs and other organs, major differences from conventional keyboards are that the individual keys are much larger, for easy manipulation by the feet, and the number of keys is much smaller, usually about four octaves or less.