The equation x² + y² = 1 represents a circle centered at the origin (0, 0) with a radius of 1. In this equation, x and y are the coordinates of any point on the circle. When you plot this equation on a graph, you will see a perfect circle that touches the points (1, 0), (0, 1), (-1, 0), and (0, -1). This equation is a fundamental example in geometry and is often used in trigonometry and calculus. It illustrates the relationship between the coordinates in a two-dimensional space and is essential for understanding concepts like polar coordinates and parametric equations.