Apple - Return vs. Enter?

On a MacBook with no number pad, the key combination fnreturn produces the Enter key. Individual programs can decide whether to treat the two keys as separate or the same. Many programs treat them the same.

The only example I have been able to come up with that still treats the two keys separately is iTunes: when browsing tracks, return starts playing the track, while enter (or fnreturn) enters track rename mode.

Maybe a bit of history is in order:

The first time a larger group of people required keyboards, these were data entry clerks, who had undergone the specialist training required to type fast.

For a typist to work without looking at the keyboard, their arms should not have to move, so you'd keep your fingers either on the home row (for alphanumeric input) or on the numeric pad. If the form requires both text and numbers, there would typically be two sections (which is why several forms ask for the city first, then the zip code, and only numbers afterwards, the origin of "1-Male/2-Female").

As a compromise between form entry and typing longer texts, the default mapping for the large key on the right of the alphanumerics area became Return, which inserts a line break; in order to advance to the next form field, Shift-Return provides another Enter key (which is why the word "Enter" is printed on the key).

This distinction has largely fallen out of use today as typing is no longer a specialist job, but computers in the home need to be intuitively understandable (rather than easy to use), and people have grown accustomed to using the Tab key to move between fields (which is actually quite cumbersome when your hand is placed so the index finger is on the f and the Ctrl key is still reachable).

Enter and Return are often interchangeable, particularly on Windows systems where the distinction is even less obvious that with some other OS.

The key is in the codes the the keys actually send when you press them - we all know what we intend, when we use those keys, but what does the computer see? The answer is that is either sees a command for New Line, or a Carriage Return.

These are 2 separate commands and they do different things - think of a typewriter; a new line is like advancing the barrel moving the paper up one line, carriage return returns the whole sheet of paper back to the left margin as well as advancing the paper up. The symbols almost reflect this; ↩ (new line and return) or ⌤ (doesn't really indicate new line, but does indicate a stationary cursor; see example later)

Now, sometimes (Yep, Windows) no matter what you input, you get a carriage return, as the OS doesn't distinguish between the 2. But on other OS it does give you 2 different meanings. As such, an Enter is often used to move onto the next item, with Return signifying an end to the input and a return to the beginning. The difference between the 2 in many programs might be something like the following:

Dear Sirs,⌤
          What's the difference between Enter and Return?⌤
                                                         Many Thanks,⌤
                                                                     Stuffe⌤

Or

Dear Sirs,↩
What's the difference between Enter and Return?↩
Many Thanks,↩
Stuffe↩

There isn't quite such a clean analogy on modern systems, but that's the historical starter for 10. This then get's muddled by the fact that, actually these days we often use TAB in place of Enter, think of filling a web form in.