Capitalization Rules and Acronyms

August 24, 2005 5:57 PM

I'm trying to figure out the proper capitalization rules for acronyms.

Best explanation I've found so far is over at NASA. The only thing I'm not clear on is what they mean by "proper name". Obviously, in the title of a document the usual capilization rules apply but I'm talking about in the middle of a sentence. For example, is it "The dynamic host configuration protocol ..." or "The Dynamic Host Configuration Protocol ..." and why?

More examples:
* Read-Only Memory or read only memory?
* Personal Computer or personal computer?

Is there a particular set of rules for technical abreviations vs non technical ones?

Maybe this is obvious to native writers but I'm having trouble pinning down the diffrence. Any help would be appreciated.

posted by cm to Writing & Language (16 answers total)

If you are going to acronym it, then capitalize it to indicate which letters form the acronym. If not, don't, unless it is a proper noun, which would be capitalized regardless.

E.g. "Your computer starts up from Read-Only Memory (ROM). The ROM contains diagnostics and instructions and for reading a bootstrap program from disk."

But "Your computer starts up from read-only memory, which contains diagnostics and instructions for reading a bootstrap program from disk."
posted by kindall at 6:10 PM on August 24, 2005

"Dynamic Host Configuration Protocol" is, to be clear, a proper noun -- it is a specific protocol, not just any dynamic host configuration protocol. Similarly, Internet is always capitalized when it refers to a specific internet (the public one).
posted by kindall at 6:12 PM on August 24, 2005

Response by poster: If you could be kind enough to quote a style reference that would also be helpful. I'd like to be able to cite this inorder to prove my use and "well, kindall on metafilter said so" doesn't work.
posted by cm at 6:30 PM on August 24, 2005

To clarify what I think/hope kindall is saying in the grammatically incorrect last sentence in his first post (;)), only capitalize non-specific things if you're explaining and using the acronym from there on; otherwise, use the lowercase versions.

Think of it like a car...you'd never say "Now, lift up the Hood and look at the Engine Block" or "Perhaps your Brakes are shot" (unless you were one of those ghastly and all-too-common-on-the-Internets folks who just don't bloody know how to write their own damned language).

And you could easily get away with saying "Perhaps your anti-lock braking system failed". But, since "anti-lock brakes" is often used in acronym form as ALB or ABS, saying Anti-Lock Brakes or Anti-lock Braking System is okay, provided you're using it like this :)

So, for your own examples, saying "Personal Computer" is exceedingly rare unless you're explaining what 'PC' means to someone who's been living under a rock for fifteen years; saying "personal computer" is far more common.

Saying "Read-Only Memory" is, again, only used when explaining what ROM stands for to someone who's not a computer geek; if someone uses that capitalization instead of "read-only memory" in a technical paper, they're either being far too formal or they're one of the people I lambasted above re: poor writing skills.

I have now wasted entirely too much time explaining a simple concept and will henceforth depart for a mind-numbing entertainment activity. Hope this helped! Also, any overt nastiness in my tone is your imagination, so please don't be offended (seriously!) :)
posted by cyrusdogstar at 6:36 PM on August 24, 2005

I don't know offhand of any official sources (such publications are notoriously bad at keeping up with technical stuff) but it's possible that Strunk & White or other books on the same site there, might help. No idea if S&W talk about this particular issue, I rather doubt it, but that's the only related bookmark I have handy.
posted by cyrusdogstar at 6:39 PM on August 24, 2005

The Guardian Style Guide is very good for this sort of thing.
posted by blag at 6:57 PM on August 24, 2005

I don't remember if acronyms are in Strunk & White, but I know many of these cases are covered in The AP Stylebook. I remember being vigorously quizzed on this stuff in copyediting class in j-school. Bleh.
posted by bcwinters at 7:13 PM on August 24, 2005

There's an important, somewhat subjective rule that I applied when I was a tech writer. If your audience is familiar with an acronym, there's no reason to write it out.

For example, if you're developing a tool for Web designers, there's no reason to write out HTML. A small consideration, but a handy rule.
posted by dbarefoot at 7:20 PM on August 24, 2005

From the Guardian stylebook:

Use all caps only if the abbreviation is pronounced as the individual letters; otherwise spell the word out

N.B.: I've only seen this in British English -- UK newspapers refer to "Nasa", "Nato", and "Aids", where US ones will use "NASA", "NATO", and "AIDS."
posted by Vidiot at 8:52 PM on August 24, 2005

In the NASA guide you quote from, "proper name" means any proper noun. Basically, that's anything which is a unique entity, such as people and organisations.

The example you use is only an initialisation, so you would always use all capitals for the abbreviation (i.e. DHCP) but I'm not sure whether you would consider the protocol a proper noun. I think probably, so you would use capital letters when writing the term out in full.

An acronym is an initialisation which forms another word -- like radar and laser. The extent to which the acronym has been absorbed into common speech usually determines whether or not you would write it normally or use capital letters. If the acronym is a proper noun, like the examples Vidiot gives, you have to decide whether to treat it as a standard proper noun (e.g. Nato) or an initialisation (NATO).

I'm not sure why the US and UK would do things differently, but it's probably just an editorial preference of the respective publications (I notice that my Collins dictionary says that NATO and Nato are equally acceptable).

If in doubt, check the dictionary or a good style guide -- the Chicago Manual of Style in the US and the Oxford Manual of Style in the UK are good places to start.
posted by londonmark at 3:14 AM on August 25, 2005

There's the Tech Web Encyclopedia.

And off-topic but related: Acronym Finder.

Don't use AP style as gospel, unless you're writing for a newspaper. Their style is in conflict with accepted tech-writing usage in several areas. See this page, for instance, where it dictates, On first reference, don't put an abbreviation or acronym in parentheses after an organization's name. That's exactly what everyone else does.

The real answer is no, there is no one set of rules for technical abbreviations. If the people you're writing for have a style guide, follow it. If they don't, find one that seems comprehensive and consistent with what you're used to, and use that.

Microsoft publishes a style guide that some people like. I am not one of those people, partly because their style guide has numerous conflicts with their own computer dictionary.
posted by Kirth Gerson at 4:02 AM on August 25, 2005

Thanks, Vidiot -- so that's why they do that. It's the difference between an acronym and an abbreviation, and apparently the British are instructed to mark acronyms by capitalizing only the first letter. Totally wrong, IMO; nor do I care for the New Yorker's style of never omitting the periods, whether acronym or abbreviation. (But I do prefer the British style of dropping the period in Mr or Mrs .)
posted by Rash at 9:26 AM on August 25, 2005

But I do prefer the British style of dropping the period in Mr or Mrs

Incidentally, I believe this stems from the difference between an abbreviation and a suspension. A suspension takes letters out of the middle of a word (i.e., first and last letters are the same), while an abbreviation truncates the word. I read once that abbreviations have periods after them, but suspensions don't.

Again, I've only seen this in British English.

(And the New Yorker's stylebook eccentricities would make a wonderful FPP in themselves...)
posted by Vidiot at 10:01 AM on August 25, 2005

Best explanation I've read is in Bill Walsh's The Elephants of Style. This excerpt is from pages 30-31, but there are several sections in the book on acronyms and initialisms. I'd recommend picking it up.

"An acronym is a word made up of initials or syllables from a combination of other words. HUD is an acronym, because it's pronounced as a word: 'hud.' HHS is an initialism, because it's pronounced letter by letter: 'H-H-S.'

"A few common-noun acronyms have truly become words and lost their capitalization altogether--scuba comes from self-contained underwater breathing apparatus.... As for capitalized acronyms, ideally they should be all caps only if each letter actually stands for a word. NATO is North Atlantic Treaty Organization, but what the U.S. Army calls CENTCOM should be Centcom in a well-edited publication. It stands from Central Command, not, say, Collection of Enlisted Ninjas Taking Care to Obliterate the Masses.

"Unless you're deeply enough committed to this principle that you don't mind eliciting some head-scratching, however, you do need to allow for a grandfather clause of sort for a few well-know acronyms that shouldn't be all caps but have written that way so extensively as to be entrenched....

"Some stylebooks establish an arbitrary length at which an acronym can no longer be all caps. For the New York Times and the Wall Street Journal it's five letters or more, so Unicef, Unesco and other acronyms that most people are used to seeing in all caps are treated differently in those newspapers.

"Of course, I'm writing from an American English viewpoint. British English, for the most part, treats true acronyms as words and not initials. In British, NATO is Nato."
posted by Sully6 at 11:37 AM on August 25, 2005 [1 favorite]

Oops, I left out this paragraph, which answers another one of your questions:

"The mere existence of an acronym or initialism has no bearing on whether spelled-out word is capitalized. Joint Photographic Experts Group is a proper noun, but acquired immune deficiency syndrome and individual retirement account are not."
posted by Sully6 at 11:42 AM on August 25, 2005

The mere existence of an acronym or initialism has no bearing on whether spelled-out word is capitalized

Thank you. That was driving me crazy.

There's no way to "figure out" this stuff; pick a style guide that appeals to you (Chicago is the most widely used in the US) and follow its rulings. These matters are purely arbitrary, and that's the only way to be consistent.
posted by languagehat at 3:00 PM on August 25, 2005