Define the circle segment and sector of a circle.

Circle Segment: A chord of a circle divides the circular region into two parts. Each part is called as segment of a circle.

The segment containing minor arc is called the minor segment.

The segment containing major arc is called the major segment.

Sector of a Circle:

The circular region enclosed by an arc of a circle and the two radii at its end points is known as sector of a circle.

The smaller sector OALB is called the minor sector.

The greater sector OAMB is called the major sector.