The keyboard that came with the IBM 5150 was an extremely reliable and high-quality electronic keyboard originally developed in North Carolina for the Datamaster.
Each key was rated to be reliable to over 100 million keystrokes.
For the IBM PC, a separate keyboard housing was designed with a novel usability feature that allowed users to adjust the keyboard angle for personal comfort.
Compared with the keyboards of other small computers at the time, the IBM PC keyboard was far superior and played a significant role in establishing a high-quality impression.
For example, the industrial design of the adjustable keyboard, together with the system unit, was recognized with a major design award.
Byte magazine in the fall of 1981 went so far as to state that the keyboard was 50% of the reason to buy an IBM PC.
The importance of the keyboard was definitely established when the 1983 IBM PCjr failed commercially, in large part for having a much different and mediocre "Chiclet keyboard" that made a poor impression on customers.
Oddly enough, the same thing almost happened to the original IBM PC when during early 1981 management seriously considered substituting a cheaper and lower quality keyboard.
This mistake was avoided on the advice of one of the original development engineers.

However, the original 1981 IBM PC 83-key keyboard was criticized by typists for its non-standard placement of the Return and left ⇧ Shift keys, and because it did not have separate cursor and numeric pads that were popular on the pre-PC DEC VT100 series video terminals.
In 1982, Key Tronic introduced a 101-key PC keyboard, albeit not with the now-familiar layout.
During 1984, IBM corrected the Return and left ⇧ Shift keys on its AT keyboard, but shortened the Backspace key, making it harder to reach.
In 1986, IBM introduced the 101 key Enhanced Keyboard, which added the separate cursor and numeric key pads, relocated all the function keys and the Ctrl keys, and the Esc key was also relocated to the opposite side of the keyboard.
The Enhanced Keyboard was an option for the PC XT/AT in 1986, both of which were also available with their original keyboards, and introduced the key layout that's still the industry standard.

Another feature of the original keyboard is the relatively loud "click" sound each key made when pressed.
Since typewriter users were accustomed to keeping their eyes on the hardcopy they were typing from and had come to rely on the mechanical sound that was made as each character was typed onto the paper to ensure that they had pressed the key hard enough (and only once), the PC keyboard used a keyswitch that produced a click and tactile bump intended to provide that same reassurance.

The IBM PC keyboard is very robust and flexible.
The low-level interface for each key is the same: each key sends a signal when it is pressed and another signal when it is released.
An integrated microcontroller in the keyboard scans the keyboard and encodes a "scan code" and "release code" for each key as it is pressed and released separately.
Any key can be used as a shift key, and a large number of keys can be held down simultaneously and separately sensed.
The controller in the keyboard handles typematic operation, issuing periodic repeat scan codes for a depressed key and then a single release code when the key is finally released.

An "IBM PC compatible" may have a keyboard that does not recognize every key combination a true IBM PC does, such as shifted cursor keys.
In addition, the "compatible" vendors sometimes used proprietary keyboard interfaces, preventing the keyboard from being replaced.

Although the PC/XT and AT used the same style of keyboard connector, the low-level protocol for reading the keyboard was different between these two series.
The AT keyboard uses a bidirectional interface which allows the computer to send commands to the keyboard.
An AT keyboard could not be used in an XT, nor the reverse.
Third-party keyboard manufacturers provided a switch on some of their keyboards to select either the AT-style or XT-style protocol for the keyb
The keyboard that came with the IBM 5150 was an extremely reliable and high-quality electronic keyboard originally developed in North Carolina for the Datamaster. Each key was rated to be reliable to over 100 million keystrokes. For the IBM PC, a separate keyboard housing was designed with a novel usability feature that allowed users to adjust the keyboard angle for personal comfort. Compared with the keyboards of other small computers at the time, the IBM PC keyboard was far superior and played a significant role in establishing a high-quality impression. For example, the industrial design of the adjustable keyboard, together with the system unit, was recognized with a major design award. Byte magazine in the fall of 1981 went so far as to state that the keyboard was 50% of the reason to buy an IBM PC. The importance of the keyboard was definitely established when the 1983 IBM PCjr failed commercially, in large part for having a much different and mediocre "Chiclet keyboard" that made a poor impression on customers. Oddly enough, the same thing almost happened to the original IBM PC when during early 1981 management seriously considered substituting a cheaper and lower quality keyboard. This mistake was avoided on the advice of one of the original development engineers.
However, the original 1981 IBM PC 83-key keyboard was criticized by typists for its non-standard placement of the Return and left ⇧ Shift keys, and because it did not have separate cursor and numeric pads that were popular on the pre-PC DEC VT100 series video terminals. In 1982, Key Tronic introduced a 101-key PC keyboard, albeit not with the now-familiar layout. During 1984, IBM corrected the Return and left ⇧ Shift keys on its AT keyboard, but shortened the Backspace key, making it harder to reach. In 1986, IBM introduced the 101 key Enhanced Keyboard, which added the separate cursor and numeric key pads, relocated all the function keys and the Ctrl keys, and the Esc key was also relocated to the opposite side of the keyboard. The Enhanced Keyboard was an option for the PC XT/AT in 1986, both of which were also available with their original keyboards, and introduced the key layout that's still the industry standard.
Another feature of the original keyboard is the relatively loud "click" sound each key made when pressed. Since typewriter users were accustomed to keeping their eyes on the hardcopy they were typing from and had come to rely on the mechanical sound that was made as each character was typed onto the paper to ensure that they had pressed the key hard enough (and only once), the PC keyboard used a keyswitch that produced a click and tactile bump intended to provide that same reassurance.
The IBM PC keyboard is very robust and flexible. The low-level interface for each key is the same: each key sends a signal when it is pressed and another signal when it is released. An integrated microcontroller in the keyboard scans the keyboard and encodes a "scan code" and "release code" for each key as it is pressed and released separately. Any key can be used as a shift key, and a large number of keys can be held down simultaneously and separately sensed. The controller in the keyboard handles typematic operation, issuing periodic repeat scan codes for a depressed key and then a single release code when the key is finally released.
An "IBM PC compatible" may have a keyboard that does not recognize every key combination a true IBM PC does, such as shifted cursor keys. In addition, the "compatible" vendors sometimes used proprietary keyboard interfaces, preventing the keyboard from being replaced.
Although the PC/XT and AT used the same style of keyboard connector, the low-level protocol for reading the keyboard was different between these two series. The AT keyboard uses a bidirectional interface which allows the computer to send commands to the keyboard. An AT keyboard could not be used in an XT, nor the reverse. Third-party keyboard manufacturers provided a switch on some of their keyboards to select either the AT-style or XT-style protocol for the keyb
IBM Personal Computer