Time
Brits always use the 24 hour clock and it’s too hard to understand.
OK, in case you did not realise, a day is 24 hours. Twelve are AM and twelve are PM. It’s not a complicated system and if you have problems with it, they are your problems.
Times are written as four digits eg 1147. Anything more that 1200 is PM and you can convert to 12 hour time by subtracting 12 from the first two digits, so 1800 is 6.00pm (because 18 – 12 = 6).
Do we use the 24 hour clock? No, we don’t.
If I am meeting you for drinks at 7 o’clock tonight, I won’t say 1900 hours. Nor will I say 7pm. I will say ‘7 tonight’.
There are circumstances where a 24 hour clock is advantageous. We Brits, and most of the rest of the world, cope with it easily. Our timetables don’t get complicated with having AM or PM printed on, or bold or non-bold type, to avoid ambiguity. We just use 24 hour times.
It’s easy and it’s not confusing.
Airlines/airports do it, all transport does it, anything where you want to be clear and consistent.