DEC VT220

Escape Key controversy

Prior to the VT220, if an Escape key was present, it was positioned in
the upper left corner of the keyboard. The VT220 moved it to the typical
location for the f11 key, in the middle of the top row of keys. For
users of the TECO editor, in which it is heavily used, this was
inconvenient.[7][8] 


Legacy

In 1983-1984, during the design phase of the IBM Model M keyboard, the
VT220 was a new and very popular product. IBM's design team chose[9] to
emulate its LK201 keyboard layout. Key innovations that IBM copied were
the inverted-T shape of the arrow cluster, the navigation keys above it,
and the numeric keypad off to its right. Eventually the popularity of
the IBM PC would lead to the Model M layout becoming standardized by
ANSI and ISO. Through those standards, minor variations of the VT220's
keyboard layout have dominated keyboard design ever since.