In primary school mathematics, circle is one of the basic geometric figures, which belongs to two-dimensional figures. A circle is a set of all points on a plane equidistant from a point (center). This is how the circumference is formed. Circle is often used to calculate area and perimeter, which is a very important geometric concept.

Circles are usually used to solve problems related to circles. For example, in a math course, students need to learn how to measure the diameter, radius and circumference of a circle. Some characteristics of a circle are also very important, such as arc, central angle and sector. Mastering these concepts and skills can help students better understand and solve problems related to circles. They are also often used in engineering and science.

Understanding the concept and basic characteristics of circle can have a positive impact on students. It can not only improve students' math skills, but also promote their logical thinking and creative thinking. The circle is a widely existing shape in our life. It has many applications not only in mathematics, but also in daily life. Mastering the knowledge of circle can also improve students' ability to know and understand things around them.