### Theory:

Geometry derives from the Greek word 'earth measurement', which is the mathematics branch concerned with the properties and relationships of points , lines, surfaces, solids, and analogs of higher dimensions.
A specific position or location on the surface of the plane is referred to as a point. The above figure shows point $$A$$ and $$B$$.

A point is sort of an invisible dot that may determine a location/position but can't be extended. To represent the location/position, we label each point using an English alphabet.
Example:
We are planning to locate the five-place (let them be $$A$$, $$B$$, $$C$$, $$D$$ and $$E$$) on a map using the concept of points and label them accordingly. When a line is drawn between the two points, it is referred to as a line segment. The above figure shows a line segment $$AB$$ and is represented as $\overline{\mathit{AB}}$.

A line segment is used to determine the distance between two points.
Example:
We are planning to demonstrate the distance between the five places (let them be $$A$$, $$B$$, $$C$$, $$D$$ and $$E$$) on a map using the concept of a line segment and label them accordingly. Here the distance between $$A$$ and $$B$$ is shown by drawing a line between $$A$$ and $$B$$. Similarly, the distance between $$B$$ and $$E$$, and the distance between $$C$$ and $$D$$ are shown in the following picture. A line may be a combination of points that extends infinitely in both directions. A line is labelled sort of a line segment with a bidirectional arrow over the label. The above figure shows a line $$AB$$ and is represented as $\stackrel{↔}{\mathit{AB}}$ or $\stackrel{↔}{\mathit{BA}}$.
Example:
$$100$$ metres track is to illustrate the concept of the line. A track may be a line that extends infinitely in both the direction without having a fixed starting and ending point. When three or more points lie on the same line are called collinear points. The above figure shows the collinear points $$A$$, $$B$$ and $$C$$. These points are collinear points because all three points lie on the same line.
Example:
Arrange the more number of cups to validate the concept of the collinear points. A ray is often defined as a straight line that starts from a point and extends indefinitely in one direction.
The starting point that's fixed at one end is termed as a vertex of a ray. Ray is additionally one-dimensional entity as we will move endlessly in one direction alone. The above figure shows a ray $$AB$$ and is represented as $\underset{\mathit{AB}}{⟶}$.
Example:
We have a battery-operated torch on one end of the road and light from the torch (called as a line segment) is travelling in a straight line towards the other direction. Since we don't know the end of that light, we will say that this line segment from a fixed source may be a ray. 