Which tool is typically used to draw a circular curve?

The tool typically used to draw a circular curve is the compass. A compass is specifically designed for this purpose, as it has two arms: one with a pointed end to anchor the compass at a specific point, and the other with a pencil or drawing instrument to create the curve at a consistent radius. This allows for precise and smooth circular arcs to be drawn, which is essential in fields such as drafting and surveying.

In contrast, a ruler is primarily used for straight lines and measuring distances and lacks the capability to create curves. A protractor is useful for measuring and constructing angles but is not designed for drawing circular curves. Similarly, a caliper is mainly used for measuring the distance between two opposite sides of an object and does not have the functionality required for drawing curves. The unique design and specific function of the compass make it the ideal tool for this task.