Functional testing
Also called: functional QA, black-box testing
Functional testing checks that a product does what it is supposed to do for its users, judged from the outside, by behaviour.
Functional testing exercises a product the way its users do and compares what happens with what should happen. It covers journeys from start to finish across web, mobile, back office and the services behind them.
It is sometimes described as the unskilled part of QA, to be automated away. In practice it is where judgement lives: knowing which journeys matter, what a correct result looks like and what the user will make of an error.
My work is functional first. Technical checks on APIs, performance and security support it, and I use AI to speed those up, so that my time goes on journeys, acceptance and the release decision.