Trigonometric functions are mathematical operations that are used to study the relationships between the sides and angles of triangles. The word "trigonometric function" can be replaced by several synonyms such as circular function, periodic function, or simply trig function. These functions include sine, cosine, tangent, cotangent, secant, and cosecant. They are often used to model phenomena that involve periodic cycles, such as sound waves or the movement of planets. In addition, they are also used in a variety of scientific fields, including physics, engineering, and computer graphics. Understanding the properties of trigonometric functions is essential for solving complex mathematical problems and developing practical applications in these and other disciplines.