Unemployment Rate, explained.
The share of the labour force that is out of work and looking for a job.
Why it moves markets
A tight labour market tends to push wages and inflation up, which can make a central bank keep rates higher for longer. A rising rate can signal a slowdown. Markets react to the gap between the figure and what economists expected.
Who publishes it, and when
National statistics agencies (e.g. BLS in the US, ONS in the UK, ABS in Australia, Stats SA). Monthly in most economies; quarterly in some (e.g. South Africa, New Zealand).
Pairs that often react
Pairs that include the currency involved usually react most. How much and in which direction depends on the surprise against expectations and on everything else going on. This isn't a prediction.
Educational only. Not advice and not a signal. Spreads often widen and prices can gap around big releases.