We're a weird country. We decimalised our currency, our weights and measures in shops and science, but we can't let go of imperial measures. Amongst the general population, people are far more comfortable talking about miles and miles per hour, than kilometers. Land sizes are still measured in acres and hectares. If you ask anyone their height, you'll probably get an answer in feet and inches, but ask their weight and they're more likely to tell you in kilograms rather than pounds and stone.

Doesn't this get confusing when all traffic and road signs, car instruments, etc. are in miles and miles per hour?

Those small blue signs at the side of motorways, and the white emergency location posts, both use kilometres.

Yeah, the thing with imperial units and engineering is that once you get anywhere near mass, weight, force, anergy, and all the related units for same, it can get very confusing and error prone. So are we talking pounds-mass, pounds-force, or slugs? (The latter being something that probably no one who didn't take engineering/physics/etc. classes has ever heard of.)

We're an eccentric bunch!

If I were measuring a space to cut something to fit I would use inches or feet and inches, 23 an 1/8, for instance.

I might need a small hole about 1/8 of an inch, open my drill box and select a 3mm.

If I were ordering timber I might ask for a 3 metre length of 4x2. As in 4x2 inches! If 3m were too long you might prefer an 8ft length. The yardman would walk you straight to the 2.4m pile without hesitation. Of course timber lengths are in 300mm increments to align with the feet of old. When you got your despatch note it would say something like 2400x100x50. Or perhaps they used regularised timber and it would have been machined down to 97×47 which may or may not be mentioned on the ticket. It would still be called 4x2 whatever!

Thing is, none of this caused us any trouble whatsoever. Well.. apprentices who learnt cm at school (which was NEVER used in construction) had a fun few weeks at the beginning.

I had engineers use all the same terms to me verbally, but never in their written work which were always in mm

You could call 24 Crown and a Drown and 360 of those would be a Yawn. Throw in 5 or 6 extra Drown every Yawn, and you'd add a Drown to the 4th, 6th, 7th, and 11th Shawn of the Yawn, but subtract two Drown from the second Yawn, if you're electing a president, and then only subtract one, cuz Merica!

I think they didn't. It is a mix of colloquialisms of different origins (one farthing is "one fourth-ing" said too many times) but some might have been localized versions, etc or just used in specific situations.

So I'm pretty sure most people knew some of those but not all of them.

But if you think about it penny/nickel/dime etc is also confusing. Less confusing but still. Just tell me I'm 15 cents short or something like that.

Mite doesn't have a standard definition. My unabridged Oxford dictionary says it was just a very small amount of money, and people gave it various definitions.

Copper means any copper coin, it's never been specific to a one penny coin. Currently it means the copper-coloured coins, 1p or 2p.

Groats as coins worth four pence were last issued in 1662, and according to the OED later 4 pence coins were called fourpence or fourpenny bits/pieces, including in casual speech.

Most of the words are straightforward fractions or multiples of a penny, with optional slurred pronunciations:

       ¼ penny = farthing
       ½ penny = halfpenny or ha'penny
       1 penny, usually abbreviated as 1d
       2 pence = tuppence
       3 pence = thruppence, thre'penny bit
       4 pence = fourpence piece, fourpenny bit
       6 pence = sixpence (slang: tanner)
      12 pence = 1 shilling (slang: bob)
   2 shillings = 1 florin (slang: two bob bit)
         2s 6d = half crown
   5 shillings = 1 crown
  20 shillings = 4 crowns = 1 pound
  21 shillings = 1 guinea

Just like the USA, where a movie ticket presumably once cost a nickel, then a dime, but then 15 cents. (Although none of the old words above are in standard usage in Britain.)

As someone else mentioned, us Brits still use imperial measurements (to some extent) and I get by just about.

In fact, the £ sign is a stylized letter L, and the system is really Lsd: libra (meaning, amongst other things, pound in Latin), solidus, denarius. This is the Carolingian monetary system and, as the name suggests, goes back to the Holy Roman Empire - as early as the 8th century.

That includes the L 1 = 20 s = 240 d ratio that made its way to pre-decimalization British currency.

They stopped minting groats (4d) after 1856 (except in Maundy money), half-farthings after 1870, and farthings after 1956. Farthings and silver thrupnies (3d) were still around but not in circulation.

The florin (2/-, or a tenth of a pound) was introduced during the first attempt at decimalization in 1849.

Crowns (5/-) were never in circulation, but were minted for special events such as coronations. They still are, but their face value is now £5.

Decimalization began in 1968 with the introduction of 5p and 10p coins (same size and value as 1/- and 2/- coins) followed by the 50p coin (10/-) in 1969. It was completed in 1971 with the introduction of the 1/2p, 1p, and 2p coins.

From secondary school onwards, it was decimal money and metric/SI units, which simplified calculations a bit.

Ireland decimalized at the same time as UK, and Australia and New Zealand a few years earlier (at the rate of two dollars to one pound).

Also known as half a crown, or two-and-six.

Twelve (pence to the shilling) is actually quite a convenient way of denominating money. Twelve has more divisors than ten, which makes a lot of calculations easier. It wasn't so hard to learn the basics - 12 pence to the shilling, 20 shillings to the pound; a child could do it. But working out 17.5% VAT on a transaction in decimal coinage isn't so much fun.

Frustratingly, the article doesn't say! For example, could the reason for the weird fractions be coin cutting? [1]

[1] "Medieval Cut Pennies" https://www.cointalk.com/threads/medieval-cut-pennies.266902...