I've done a lot of work on tags lately and I'd like to share with the community some thoughts about the way tags should be named so that maybe it could become part of the FAQ and so hopefully lead to a more uniform tagging practice.

• Acronyms should be spelled in all uppercase. This to avoid confusion with possible words (e.g. led vs. LED, can vs. CAN) and to make them stand out.

• The main tag for acronyms should be the acronym itself, not the spelled-out form. This latter should be added as a synonym, i.e. don't leave an acronym tag lacking the spelled-out form, do add it as a synonym. For example LED (tag name) and light-emitting-diode (synonym), not vice versa. This because almost always the acronym is more recognizable and it is what most people know about (some people don't even know what an acronym stands for). Moreover, it is shorter and this is good for the UI presentation. Spelled-out form(s) should always be added (as synonyms) to avoid another, separate tag to be created by another user.

• Otherwise tags should be all lowercase words separated by hyphens. This to ensure uniformity and wildly varying capitalization differences. This should be valid also for spelled-out acronyms, e.g. LED, but light-emitting-diode, not Light-Emitting-Diode.

• Exception: Only a person's name should be capitalized. This to convey the information that a word is not some technical term, but it is the name of a person. This can be important because people with different linguistic backgrounds can be misled. For example, Darlington-pair and not darlington-pair, because of Mr.Darlington not being some funny English word whose meaning eludes the reader. If some English native speaker is not convinced, try it out with some non-English name: Giacoletto-model, Dirac-delta, Popov-method, Routh-method, Ohm-law, Gauss-theorem (try to forget for a moment you maybe already know those people from your past studies and try to picture their name as a "plain" English word).

• The words should always be spelled out in singular form. This to avoid a mixup of singular and plural tags. E.g. LED and not LEDs, transistor and not transistors, operational-amplifier and not operational-amplifiers. This could be debatable, but IMO its the most sensible choice, since most terms make sense also in singular, but the contrary is not always true. There can be exceptions to this rule when the tag without the plural doesn't make sense, for example Maxwell-equations and not Maxwell-equation (they are more than one), but Shockley-equation (it's just that one). The same for Kirchhoff-laws and not Kirchhoff-law.

• Saxon genitives should be suppressed. This to avoid entering tags with an apostrophe and, if someone entered the tag without the apostrophe, to confuse it with a plural form (see previous rule). E.g. Kirchhoff-laws and not Kirchoffs-laws or Kirchoff's-laws, Maxwell-equations and not Maxwells-equations or Maxwell's-equations, Gauss-theorem and not ... what? Gausss-theorem? Gausses-theorem? Gauss'-theorem? Simply drop the genitive and be done with it, much less hassle and much more uniformity.

• No adjective-only tags, they can be very misleading. For example, what does binary (actual tag) refer to? Binary numbers? Binary transmission? The same goes for serial (Communication? Interface? Bus? Serial number?), adjustable (Regulator? Parameter?), linear (Model? System? Amplifier? Regulator?), thermal (Protection? Resistance? Design?), resettable (System? Fuse? Protection?) or electrical!

• No ambiguous tags. This is similar to the previous rule, but its applicable to nouns. Whereas adjective-only tags are almost always a problem, single-noun tags can be perfectly fine. However some nouns, often used as adjectives with other nouns, can have the same problems. For example: flyback (Transformer? Power-supply?), high-speed (Design? Opamp? Signal? Communication? Bus?). And then there are nouns so general to be ambiguous in itself zero (The number? The root of an equation? "Zero" as in "pole-zero diagram"? Some kind of reference level?).

The previous were essentially hard-and-fast rules that are easy to check without too much thinking, except for some corner cases. I devised them based on common sense, engineering practice and the premise that tags should help group questions with somewhat similar topics.

In other words, tags shouldn't be some kind of "keyword" systems that just helps in searching a question. They should convey "structure". Please correct me if I'm wrong on this and I have misunderstood the feature.

EDIT (numeric values in tags)

Because of the posts of Olin Lathrop and Lundin I realized my proposed guidelines missed something important: a rule about quantities. I propose the following to be added.

• Tag names containing numeric values should be avoided if possible. That's because in general they don't convey particular structure to the questions. If a value is central to a set of questions it probably already has a name (e.g. π, ε₀).

• If a tag must contain a numeric value, it should contain the proper SI unit symbol, with correct capitalization as mandated by SI (e.g. 4mA, 12V). The ASCII dot "." must be used as decimal separator (e.g. 3.3V) and the ASCII hyphen "-" must be used if a range of values needs to be specified (e.g. 4-20mA-loop).

• A tag containing a numeric value should also contain other words to better specify what the value refers to. E.g. 4-20mA-loop, not 4-20mA; 12V-system, not 12V; 3.3V-tolerant, not 3.3V.

I'd like to avoid EE "jargon" values like 3V3 or 4R7 to represent 3.3V or 4.7Ω. This could be confusing for the newbie (remember, tags should avoid ambiguities and be as clear as possible).

As for SI prefix and units that can't be represented with basic ASCII characters, I think we should suspend our judgement until more information is gathered from tech staff.

Olin suggested to use HTML entities like μ for μ and Ω for Ω, which would be good in principle. However I feel there could be technical problems in some browsers and users may not be aware of what an HTML entity is. If someone experienced problems with entities they could bring more harm than good, with people trying to find workarounds that could mess-up tags.

For example, I think I read somewhere any Unicode "char" could be used in tags. So someone could use different code points to represent, say, Ω. In fact Unicode has Ω (U+03A9 GREEK CAPITAL LETTER OMEGA), but also (among others) 𝞨 (U+1D7A8 MATHEMATICAL SANS-SERIF BOLD ITALIC CAPITAL OMEGA), Ω (U+2126 OHM SIGN). Moreover, even HTML entities are not unique: there is also Ω Ω. So using entities could be like opening a big can of worms.

Note also that entities and Unicode chars might mess-up the sorting algorithm used to display the tag pages.

Unless we explicitly spell-out what entities are allowed and what's their use, we could have problems. In a way I would feel safer if we restricted the usable chars to (printable) ASCII alone.

So 1μF would be written as 1uF and 1MΩ would be written as 1Mohm ^[1], as ugly as that may be (at least it is guaranteed to work and it is predictable).

BTW, some standards also allow this explicitly, as mentioned in these Wikipedia pages:

micro symbol

Ohm symbol

posted 9 months ago

CC BY-SA 4.0

9mo ago

Lorenzo Donati‭

311 reputation 10 18 59 201