Each topic gathers everything the site holds on a policy area in one place: the department responsible and how it is performing, the most recent Commons votes, the bills going through Parliament, the MPs scrutinising it hardest, the editorials, and where the public stands.
Housing is the policy area where national decisions land most directly on daily life: whether a family can afford to rent, whether a young person can ever buy, whether a council can house those with nowhere to go.
Few subjects move votes like immigration, and few are argued about with less reference to the numbers.
The NHS consumes nearly a fifth of all government spending and still cannot get patients seen on time.
Defence is where the gap between what politicians promise and what they fund is sharpest.
Education shapes every life chance the state can influence, from early years to university.
Everything else a government wants to do depends on the money to pay for it, which makes the economy the area where the hardest choices are made and the most promises broken.
The welfare system is how the state supports people who cannot support themselves, through pensions, disability benefits, universal credit and the safety net beneath low-paid work.
Climate and energy policy decides both how much households pay to heat their homes and what kind of country is handed to the next generation.
Justice and policing cover the machinery that keeps order and holds people to account: the police, the courts, sentencing, prisons and the law itself.
Transport policy is felt every day in the cost of a train ticket, the state of the roads and whether a bus still runs.
Foreign affairs is where Britain decides what kind of power it wants to be in the world.
Constitutional reform is the argument about the rules of the game itself: how Parliament works, how power is held to account, and whether the system that produces British governments is fit for purpose.