The Evolution of the Enter Key: From Carriage Return to Current Terminology

When discussing the evolution of computing terminology, one might marvel at how certain key terms have transformed and persisted over time. Notably, the key we now commonly refer to as the 'enter' key was initially known as the 'return' key, carrying connotations from earlier technologies such as manual typewriters. This article delves into how and why this key was named and how its purpose evolved as technology advanced.

Historical Background of 'Carriage Return'

Originally, the key that we now call the 'return' or 'enter' key was known as the 'carriage return' key. In the context of typewriters, video terminals, and early computer terminals, this key served a specific purpose: to return the print head or cursor to the left side of the page or screen. This was particularly useful on manual typewriters where a mechanical carriage would shift to the next line, and a lever arm was needed to adjust the carriage back to the start of the line. On electric typewriters, the functionality of this lever arm was translated into a button, which served a similar purpose.

Transition from Manual to Electronic Typewriters

With the advent of electronic typewriters and early computer terminals, the functionality of the return key remained largely the same. However, the exact function began to diverge slightly from that of a typewriter prompt. In a typewriter, the return key would actually physically return the print head to the left. In computing, the return key sends a binary code (13 0D) to the computer, which then decides what action to take.

Early Computing and Terminal Design

During the early days of computing, direct interaction with computers was prohibitively expensive. Instead, terminals were used, which allowed users to fill in forms and send the data to the computer. These terminals often featured a 'Return' key and a 'Line Feed' key, reminiscent of the keys on electric typewriters. The Return key was used to submit the form, while the Line Feed key moved the cursor down to a new line.

The IBM 2260 and 3270 Terminals

The transition from 'Return' to 'Enter' began with the introduction of block mode terminals, such as the IBM 2260 series in 1964 and the IBM 3270 series in 1971. These terminals had both 'Enter' and 'Newline' keys, used for different purposes. The Enter key allowed users to edit an entire screen full of data locally, only transmitting the data to the mainframe when the Enter key was pressed. This was a crucial feature for managing user interactions efficiently, as it meant that the mainframe only had to handle one I/O interrupt per user request, not one per keystroke.

Legacy of the Carriage Return Key

Despite the shift in functionality and the introduction of the 'Enter' key, the term 'Carriage Return' persisted as a functional name for the key in early word processing typewriters and, later, on computers. This legacy term was carried forward into modern computing, where the Enter key serves a similar purpose to submit data or move to the next line, a role that is reminiscent of its origins in manual typewriters.

Thus, the transition from 'Return' to 'Enter' is a fascinating journey through technological evolution. While the functionality of the key has changed significantly over time, its name has persisted, serving as a nod to the roots of computing and its predecessors.

Keywords: carriage return, return key, enter key