Should I use the name "Enter" or "Return" key?
I'm trying to list the what various keys do inside the documentation for my CLI program, but I'm not sure what to refer to this key as. It is commonly referred to as either Enter or Return, but which is considered better UX? I was going to list it as Enter/Return, but that seems sloppy.
A Google search seems to indicate that
Enteris more prevalent. However, my laptop gives different results - while having both
returnis printed in larger text on the key and is placed closer on the key to the user.
How should I refer to this key?
To be frank, only a selected few are aware that the Enter and Return keys are not the same - whether you refer to it as Enter or Return, users will press either buttons (if they have both buttons). This is due to the fact that on very few software products the Enter and Return keys do different things (Avid's Pro Tools is the only example I can give).
My own experience is that Enter is a more popular name; "Press the return key" sounds odd, while "Press Enter" sounds natural. I fail to see anyone to whom you'll say "Press Enter" going "Hu?", while I can imagine this happening if you'll say "Press Return". But that's just me and based on my own subjective experience; perhaps in Norway they use Return more than Enter. However, as you said, a search for "Press Enter" on Google yields 15 million results, while "Press Return" yields less than a million.
If I had been you I wouldn't worry about it so much and use Enter.
The term Return is a shorthand for Carriage Return.
Originally, the term carriage return referred to a mechanism or lever on a typewriter. It was used after typing a line of text and caused the assembly holding the paper (the carriage) to return to the right so that the machine was ready to type again on the left-hand side of the paper.
The extra trivia is quite interesting and clarifies the origins - thanks for returning (hah, get it?) to add it!
Many keyboards combine both "enter" and "return" into the same button. Here's one: http://km.support.apple.com/library/APPLE/APPLECARE_ALLGEOS/HT1171/Pasted%20Graphic.png
Just a random note, Photoshop differentiates when editing text between [Enter] as a line break / carriage return, where-as the [Return] button commits your text. Just noting because Adobe's tools are a bit more widely used, and it might even be useful for some people to hear about this.