A sector in math is a portion of a circle that is enclosed by two radii and an arc of the circle. It is a pie-shaped part of a circle made of the arc along with its two radii. A sector divides the circle into two regions, namely Major and Minor Sector. The smaller area is known as the Minor Sector, whereas the region having a greater area is known as Major Sector. The shape of a sector of a circle can be compared with a slice of pizza or a pie. The area of a sector can be calculated using the formula A = (θ/360)πr^2, where θ is the central angle of the sector and r is the radius of the circle. The perimeter of a sector is the sum of the length of the arc and the length of the two radii that form the sector.