How many diameters are there? Name all the diameter of a circle?

A circle has an infinite number of diameters. A diameter is a straight line segment that passes through the center of the circle and connects two points on the circle's circumference. Since you can choose any two points on the circumference of a circle to create a diameter, there are infinitely many possible diameters. It's not practical to list them all because there are an infinite number of them.