The list of events that have already occurred and are affecting the work, each with an owner and a resolution date. Likelihood no longer applies.
An issue has happened, so the uncertainty that would have made it a risk has resolved and there is nothing left to score a probability against. What matters instead is the observed impact, which usually keeps moving after the entry is written, an owner with the authority to act now, and a date by which the effect should stop. An issue that was never on the risk register is worth noticing: one or two are ordinary, but a steady stream means risk identification is not looking far enough ahead to be doing anything.
See also
The list of events that could affect the work but have not yet, each scored for likelihood and impact, with an owner and a planned response.
A single register holding risks, assumptions, issues and dependencies, and usually decisions, with the type recorded on every line.
Where this comes up
One bar per variable, the widest at the top, all of them measured against a baseline down the middle. A tornado diagram ranks what could move an outcome, and by how much.
A risk might happen. An issue already has. That single difference decides which artefact a line belongs in, what you record about it, and who you have to tell.
Contingency reserve sits inside the cost baseline, for risks already named and priced. Management reserve sits above it, for the ones nobody named. Level and authority, not size.
Most risk registers record one number per row. The number that actually justifies spending money is the distance between two of them.