When you're checking the size of something, for instance a potential furnishing and the place you intend to put it.
A ruler is useful for many crafts, for furnishings, for storage and other purposes.
Quote Measure twice. Cut once. |
A ruler is normally stiff as opposed to a tape measurer which is normally flexible. This makes it useful as a straight edge as well as for measuring. Some rules are designed with joints so they can be folded up to require a less long space for storage.
Schools sometimes ask students to have a ruler as one of their school supplies. It can be useful for drawing, learning about measurements or as part of a math or geometry class.