In the context of plane geometry, a quadrant is a region of the Cartesian plane that is formed by the intersection of the x-axis and the y-axis). The Cartesian plane is divided into four quadrants, which are numbered from I to IV and denoted by Roman numerals). Each quadrant has its own properties and is defined by the signs of the x and y coordinates. Quadrant I is the upper right quadrant, where both the x and y coordinates are positive. Quadrant II is the upper left quadrant, where the x coordinate is negative and the y coordinate is positive. Quadrant III is the lower left quadrant, where both the x and y coordinates are negative. Quadrant IV is the lower right quadrant, where the x coordinate is positive and the y coordinate is negative. The quadrants are used to explain the position of a point on the coordinate plane.