1. The problem asks: What is length and width? 2. Length and width are terms used to describe the dimensions of a two-dimensional shape, such as a rectangle. 3. Length is typically the longer side of the shape, while width is the shorter side. 4. These measurements are used to calculate area, perimeter, and other properties of shapes. 5. For example, if a rectangle has length $l$ and width $w$, its area $A$ is calculated by the formula: $$A = l \times w$$ 6. And its perimeter $P$ is calculated by: $$P = 2l + 2w$$ 7. In summary, length and width are simply the measurements of the sides of a shape, with length usually being the longer side and width the shorter side.