In geometry, lines, rays, and angles play a significant role in understanding the relationships within geometric figures. Let's explore these concepts!

Lines are straight paths that extend infinitely in both directions. They have no endpoints and can be labeled with any two points on the line.

Rays, on the other hand, have one endpoint and continue indefinitely in one direction. A ray is named by its endpoint and any other point on the ray. For example, if we have a ray with endpoint A and a point B lying on the ray, we would call it ray AB or BA.

Angles are formed when two rays share a common endpoint. The endpoint is also known as the vertex of the angle. Angles can be measured in degrees or radians. We usually use a lowercase letter to name an angle, such as angle 'a'.

Angles can be classified based on their measurements:

• An acute angle measures between 0 and 90 degrees.
• A right angle measures exactly 90 degrees.
• An obtuse angle measures between 90 and 180 degrees.
• A straight angle measures exactly 180 degrees.
• A reflex angle measures greater than 180 degrees but less than 360 degrees.

Understanding these basic concepts of lines, rays, and angles will pave the way for comprehending more complex geometric figures and their properties.