on what invention did the modern day keyboard first appear?

The modern-day keyboard first appeared on the invention of the typewriter. The typewriter, developed by Christopher Latham Sholes and his colleagues in the early 1870s, introduced the QWERTY keyboard layout that laid the foundation for today's keyboard design. The QWERTY layout was specifically designed to prevent the mechanical jamming of keys by placing commonly used letter pairings apart, allowing for faster typing. This design was commercialized in 1874 through the Remington typewriter, which was the first practical typewriter featuring this keyboard layout. Thus, the typewriter is the invention where the modern keyboard first appeared.