LINES: - In geometry, the notion of line or straight line was introduced by ancient mathematicians to represent straight objects with nominal width and depth. Lines are an idealization of such objects, which are often described in terms of two points or referred to using a single letter.
ANGLES: - An angle is a measurement of rotation of a line about a fixed point. The fixed point is called the vertex of an angle.
Properties of Angles:-
The sum of all the angles on one side of a straight line is always 180 degrees.
The sum of all the angles around a point is always 360 degrees.