There is no standard that says keyboards must map to something and it's up to the OS to interpret what each keycode means. The keycode sent out for the "Z" key on US English QWERTY style layouts may ...

American Standard Code for Information Interchange. more commonly known as ASCII, is the standard for representing all upper-case and lower-case Latin letters, numbers, punctuations, etc as a code ...

The sequential order of ASCII data. In ASCII code, lower case characters follow upper case. True ASCII order would put the words DATA, data and SYSTEM into the following sequence. See ASCII chart.