A pint
What it really means
The standard glass of beer in a pub (568ml). "Fancy a pint?" is a common invitation that really means "let's go to the pub and chat". You must be 18+ to buy alcohol; bars may ask for ID.
Context, tips & common mistakes
The pint is the unit of British beer — ordered as 'a pint of [name], please' at the bar, with the half ('half of Coke's fine' / 'just a half for me') fully acceptable and increasingly common. Beer taxonomy in one line: lager is cold and fizzy, ale/bitter is warmer-cellared and maltier, stout is black and creamy; pointing at a tap and asking 'what's that like?' is welcomed, and many pubs offer a small taste before you commit.
The pint measure survives metrication by law — the last redoubt of imperial in daily life along with miles — and 'going for a pint' means the pub visit itself, drink almost incidental. Zero-alcohol beers on draught and in bottles are now everywhere, letting you hold a pint-shaped object through any social occasion; nobody checks the label, and 'pint of lime and soda' remains the great cheap pub survival order.