Decimal currency has been issued in Canada since 1858. I’m not sure exactly what the country was using before, but I would assume it was a mix of American and British currency. So I guess the change wasn’t too painful.
I travelled in England in the summer of '71 and often had to explain to the elderly shop keepers how the new money worked. It was fun.
You’re correct; it was both, plus Spanish dollars as well, according to A History of the Canadian Dollar, published by the Bank of Canada (warning: PDF). It seems that trying to maintain the use of British currency in Canada was doomed to failure. From page 19 of the linked document:
And 1980s, unless I’m dreaming. Same size as a Euro 1 cent coin. About as worthless too.
In a ‘look back’ TV programme in 2001 they recalled massive preparations by the Decimalisation Board for chaos and confusion - and nothing happened. With one or two grumbles people switched over peaceably enough. The unspoken subtext was the Euro, whose advent was then pending. “in thirty years time, you’ll look back and wonder what all the fuss was about”.
Would that we had seen the YK2 issue the same way. For this Uhmurican (who was at Canturbury Cathedral one Easter morning), could someone explain how many pence to a shilling, and how many shillings to a pound? Is it as ridiculous as magical money presented in the Harry Potter books?
Vlad/Igor
12 pennies in a shilling, and twenty shillings in a pound.
I’m just a little young to recall decimalisation in NZ … being about one year old at the time… but from what I recall from my folks (and my Granddad particularly) there was a fair bit of preparation done and despite some grumbling that the new system was too complicated (?!) it all went pretty smoothly.
Granddad had a bunch of the toy money that was made to teach cashiers about the new coins… our conversion system was a bit different to the UK:
1 shilling => 10 cents
1 florin => 20 cents
1 crown =>50 cents
1 pound => 2 dollars
The new coins were the same size and had the same designs on them as the coins they replaced; for many years later you could still find a shilling or a florin or a in your change, and people simply used them as 10 or 20 cent pieces.
Decimalisation day in Australia was 14 February 1966. The Reserve Bank has some information on the process here. A “catchy” character - Dollar Bill - was used in the advertising campaign, with a song set to a well-known Australian tune. I remember my parents saying that apart from the inevitable complaints from a minority, the changeover went smoothly.
I kept a set when we converted to Euros.
I lived in England during the conversion to decimalisation and don’t remember anyone making much of a fuss …
I recall that the schools had cardboard versions of the various coins for several years beforehand to get the children used to them.
Mum bought me a set of Irish decimal coins back in the 80s when the Euro was pretty far off. It lacks the large Punt coin, but the others are quite pretty in themselves, especially the funky design on the bronze coins.
I remember people continuing to refer to “shillings” after decimalisation, meaning 5 new pence. The 5p coin was identical to the shilling coin, and in fact many 1s coins remained in circulation doing service as 5p for years.
As late as 1983 (12 years after decimalisation) my head teacher told us each to bring two pounds ten to school the next day. We duly each brought in £2.10. He was mystified - he had meant to tell us to bring in £2.50 (and was convinced that he had in fact said “two pounds fifty”, but unthinkingly said “two pounds ten [shillings]” (the equivalent denomination in old money).
I can (just) remember half-farthings.
You wouldn’t get much for one of those these days. 
I lived through the change in Australia: it went pretty smoothly. I think the banks were closed for 4 days immediately before dismal guernsey was introduced.
I think the change to $1 = 10 old shillings was easier for in-the-head calculations than the British conversion. I heard that the main reason why the British did it their way was to preserve the pound Sterling as an internationally recognised currency unit. Advantages of making the cent half as big were that Australia and New Zealand did not need half cent coins (Britain had half new pence coins for a while), and the old 6d coin could be used as a new 5c coin.
Oh come on now! Aren’t you supposed to tell us it would get you a ticket to the cinema with enough left over for a bag of chips and your 'bus fare home? 
You must be pretty old. They were in circulation between 1828–1868. Wiki cite
I still refer to an amount of 25 eurocents as ‘a quarter’ even though we don’t actually have such a coin anymore.
We did consider going to a ten-shilling pound at one time, but eventually decided to bypass the shilling altogether and settle for a hundred-penny pound.
Now, of course, inflation has made a nonsense of the monetary values involved, but that’s a different issue (and would have happened anyway).
Terry Pratchett covered this in Good Omens.