§ 557 Certain issues of fact tried by court.

Here's a plain English summary:

When a case involves questions of fact that don't require a jury trial, a judge will decide them instead. This covers any factual disputes that aren't specifically set up for jury review.

The judge still has options here. Even for these issues, the judge can choose to send them to a jury if that seems like the better way to handle it. The judge can also refer the matter to another person or body to review, as allowed under the broader court rules.

In short, this rule gives judges the flexibility to decide most factual questions themselves, while keeping the door open to use a jury or outside referee when it makes sense for the case.