Short answers, pulled from the story.
The computer keyboard originated in the 1870s as a mechanism for transmitting stock market data across telegraph lines. This early device used mechanical levers to punch holes in paper tape or send electrical signals to ticker machines before evolving into a tool for typing.
American mechanical engineer Charles Krum and his son Howard developed the teleprinter between 1907 and 1910 with critical early contributions from electrical engineer Frank Pearne. These machines served as the definitive ancestors of all key-based text entry devices and bridged the gap between the mechanical typewriter and the electronic computer.
Key Tronic Corporation introduced capacitive-based switches in 1978 that achieved a price point of just 60 dollars and became the largest independent keyboard manufacturer. Over time the key travel distance shrank from 0.187 inches to 0.110 inches and the thickness of the entire unit decreased from two inches to a mere half-inch.
The ISO ANSI and JIS standards refer to the organizations issuing the relevant worldwide United States and Japanese standards respectively. Studies published as early as 1926 by Klockenberg suggested that splitting the primary key clusters into left and right halves set at an angle could keep wrists straight and reduce strain.
Unencrypted wireless Bluetooth keyboards are known to be vulnerable to signal theft where covert listening devices can sniff and record Bluetooth packets to log keys typed by the user. This vulnerability was documented in Microsoft wireless keyboards from 2011 and earlier and includes the risk of electromagnetic signatures being detected to reconstruct keys pressed.
Alternative text-entering methods include optical character recognition which converts existing text from images into editable strings and speech recognition technology used for transcribing medical or legal dictation. The rise of virtual keyboards on touchscreens and projection keyboards that use lasers to create an image of keys on any flat surface also challenge the physical keyboard.