What is the main characteristic of a chord in relation to the circle?

A chord is defined as a line segment that connects two points on the circumference of a circle. This characteristic is fundamental, as it means a chord lies entirely within the circle, extending from one point on the edge to another point on the edge. The endpoints of the chord are part of the circle, which is a key aspect that differentiates it from other lines related to a circle, such as tangents or secants.

In essence, since a chord relies on two distinct points located on the circle to exist, it inherently reflects the relationship between the chord and the circle itself, emphasizing how chords are integral parts of the circle's structure. Thus, the correct answer captures the essence of what defines a chord in circular geometry.