What about Anno Domini and BC

[Medard Urban]

I think that must by always use.

[Sean T. Smith]

I think that goes without saying. They are, so far as I'm aware, the most common ways of referring to particular years in English, and have little religious connotation, despite their etymology.

Since I'm learning Dutch, and always appreciate correction of my mistakes, I'll risk offence by alerting you to a mistake in your post. You mean to say something like "I think that they must always be used" or "I think those must always be used". 

[David Hoffman]

You all should be aware that BC and AD are Christian-oriented terms. In academic circles, at least where the Christian orientation is a possible concern (e.g., Religious Studies), it is preferable to use the euphemistic B.C.E. (before the common era) and C.E. (the Common Era). Of course, on Wikipedia such questions lead into increasingly uncivil arguments between Christians and Jews. I don't know how this will play out on CZ. ~~~~

[Derek Harkness]

This is covered in the Chicago manual of style section 9.67, 9.38 and 15.41. Many forms of date are acceptable and the choice is to a large extent left to the author to choose between BC, BCE or others such as AH as they feel appropriate.

The use of BC or similar is required to avoid confusion, but where the context is suitable, the AD may be omitted (e.g. an article about computers does not need AD in it's dates.) The Latin forms should precede the numbers. E.g. we write AD 1066 or 1066 CE but not CE 1066 and neither 1066 AD. Here are some examples taken form the manual.

Herod Antipas (21 BCE–39 CE) was tetrarch of Galilee from 4 BCE until his death.
Britain was invaded successfully in 55 BC and AD 1066.
The First Dynasty appears to have lasted from 4400 BP to 4250 BP in radiocarbon years.
Mubarak published his survey at Cairo in 1886 (AH 1306).
The campsite seems to have been in use by about 13,500 BP.
Rome, from its founding in the eighth century BCE, . . .

[Arne Eickenberg]

You all should be aware that BC and AD are Christian-oriented terms. In academic circles, at least where the Christian orientation is a possible concern (e.g., Religious Studies), it is preferable to use the euphemistic B.C.E. (before the common era) and C.E. (the Common Era).

Christocentricity is still there if one uses BCE and CE. Propagations of BCE & CE are spurious arguments, their use simple makeup and more a sign of misled political correctness than of scientific integrity, let alone religious and/or historical self-confidence: fact is that almost all clocks and societies around the world are ticking according to the (Christian) Gregorian calendar. That's why BCE and CE also stand for "before the Christian era" and "Christian era". I personally prefer the Holocene calendar… plus maybe the C&T year calendar with the Newton week. (But that's wishful thinking, I guess.)

[Greg Woodhouse]

You all should be aware that BC and AD are Christian-oriented terms. In academic circles, at least where the Christian orientation is a possible concern (e.g., Religious Studies), it is preferable to use the euphemistic B.C.E. (before the common era) and C.E. (the Common Era).

Christocentricity is still there if one uses BCE and CE. Propagations of BCE & CE are spurious arguments, their use simple makeup and more a sign of misled political correctness than of scientific integrity, let alone religious and/or historical self-confidence: fact is that almost all clocks and societies around the world are ticking according to the (Christian) Gregorian calendar. That's why BCE and CE also stand for "before the Christian era" and "Christian era". I personally prefer the Holocene calendar… plus maybe the C&T year calendar with the Newton week. (But that's wishful thinking, I guess.)

Actually, the stand for "Before the Common Era" and "Common Era", but the point remains. After all, how is the beginning of the common era determined? In my view, this is a matter of simple courtesy: if BCE and CE are generally accepted as the preferred abbreviations, what is really to be gained by insisting on BC and AD? Of course, on Unix systems, the epoch is in 1970. After all, the true beginning of the world came with the introduction of Unix.  (In truth, it's a matter of saving a few bits in timestamp storage.)

[Joe Quick]

I propose we adopt the Maya long count.  If you need help, just plug your date into the calculator. 

[Morten Juhl-Johansen Zölde-Fejér]

We will date everything before 1980 in negative numbers dating before Berners-Lee created HTTP.

[Gareth Leng]

It does seem that CE and BCE are rapidly increasing in use. I've just searched on Google for  "5th century CE" (32,000 hits) vs "5th century AD" (172,000 hits) and suspect that the relatively high hit rate for CE use does reflect a significant unease with using AD and BC. See http://www.religioustolerance.org/ce.htm for rationale and background.

So personally I'd favour CE and BCE, anticipating that these will become dominant usage. I think the only real objection to them is that they are less well known, but this seems to be changing fast.

[ASweeney]

By sheer coincidence I had to use a year "qualifier" for the first time on an article I created last night - http://en.citizendium.org/wiki/Sea_Stallion - without having seen this topic.

I was writing about a Viking longship being built (and therefore, likely, it was done by non-Christians) in Ireland (mostly Christian at the time).  Thinking about whether to use AD or CE, I decided I didn't see the relevance of using a Christian dating system; nor did I know what potential readers would be expecting.  I plumped for CE as the one least likely to offend.

Incidentally - haven't heard of AH before... link?

[Derek Harkness]

I think it should be pointed out that CE and BCE are still christian systems. It's still the exact same Gregorian calendar and the 0 point has the exact same meaning. I could conceive that the term CE could be taken as more offencive to non Christians.  The word 'common' implies that this date is 0 point event applies to all people. Clearly non Christians could say that this 0 point is not 'common' to them and so it's not their era even with the new name. As long as the system is based on the Gregorian one, it's Christian. No matter what name you put on it.

[Arne Eickenberg]

See http://www.religioustolerance.org/ce.htm for rationale and background. So personally I'd favour CE and BCE, anticipating that these will become dominant usage.

My take on this is pretty easy. If complete secularization is the goal, we should change the calendar altogether, to something that has no religious connotations. But I usually try not to follow any "trends", and this is definitely only a trend, which is shown by the fact that BCE/CE doesn't change anything except for the makeup. As long as the world adheres to the Christian calendar, and as long as the year of reference for this calendar is the alleged year of the Christ's birth (no matter how you re-label the year suffix/prefix), I will always use AD and BC. [Although it should actually read AD and AC (for ante Christum natum), but this is not really common.] The use of BCE/CE in this respect is not only a cop-out, but also an act of historical ignorance and religious intolerance against the largest religion on the planet. As it happens, the argument of "religious tolerance" has to be applied the other way around: Depending on how you want to translate the Latin tolerare, non-Christians have to "bear", "endure" or "tolerate" (in other words "respect") the fact that our and their calendar is centered on the Christ's birth. Regarding the use of CE/BCE, as admonished by the politically correct, what's there to tolerate? Some vague assumed religious feelings that are purportedly being hurt by the use of AD/BC? If I—as a person from one of the cultures influenced and shaped by Christianity—were to tolerate anything in terms of religion, it would be a change of calendar, e.g. from BC/AD to BB/AB ("before Buddha"/"after Buddha"), or to a completely secularized calendar using e.g. HE and BHE.

[Arne Eickenberg]

A few additional notes. It's interesting to see that the CE is also re-interpreted by its propagators as "Christian Era". My guess is they want to pitch the concept to traditional Christians and lure them into the secular camp.

Something very similar happened in Communist (and by political self-conception) Atheist nations like East-Germany. Like "Common Era", terms/words were invented to eradicate any religious connotations. In the GDR they used v.u.Z. and u.Z., which stand for vor unserer Zeit ("before our time") and unserer Zeit ("of our time"). So BCE/CE has a foul smack of arbitrariness, reminescent of centrally planned Communist economies and their ideologies.

Normally the German language uses v.Chr. (vor Christus; "before Christ") and n.Chr. (nach Christus, "after Christ"). The beauty is that it is often interpreted as "before/after our chronology" by German non-Christians. Accordingly, it would maybe be a much wiser approach to apply the same pragmatism to BC/AD in English, as I have noted before in a similar discussion on an article's talk page, e.g. as "Before the Current Era" and "After the Dawn of the Current Era", especially since almost everyone is writing "2007 AD" instead of "AD 2007" nowadays. Might actually save a lot of energy.

[Arne Eickenberg]

Maybe we should turn this whole thing into a CZ proposal, a general and fundamental decision for either BC/AD or BCE/CE. If the latter were chosen I would—yes—tolerate that.

[Martin Baldwin-Edwards]

This is a piece of political correctness and a waste of time.