The major offices of state and who held them. When a figure on this site moved, this is where you find out who held the brief at the time.
A note on sourcing, because it differs from the rest of the site. Every figure on the dashboard comes from an official statistical release. This page does not: it is compiled from Wikipedia's office succession lists, which are a secondary source. Those lists are heavily scrutinised and generally cite primary records, and every entry links to the list it came from so you can check it. One date, on the current Prime Minister, has since been confirmed against the UK Parliament API. Where a primary record is available it takes precedence and this note will change.
Cabinet level only. Junior ministers, whips and law officers are deliberately excluded: including them would run to thousands of appointments and make the page unusable, which defeats the point of a reference. Departments are renamed, merged and split constantly, so each office records what it has been called and when. Where a source shows a gap of a few days between holders, the gap is kept rather than filled in.