# Line

In geometry a line:

- is straight (no bends),
- has no thickness, and
- extends in both directions without end (infinitely).

A line has **no ends** !

## Play With It

Change the position of points **A** and **B**. Note that the line **AB** extends forever in both directions:

images/geom-line.js?mode=line

## Line Segment

When it

**does**have ends it is called a "

**Line Segment**".

## Ray

When it has just **one end** it is called a "**Ray**"

## This is Cool

Now play with this one ... point "C" is made to always be an **equal distance from point "A" and "B"**. The result is a line (all the possible position of point "C" make a line):

images/geom-line.js?mode=equi

## Point, Line, Plane and Solid

A Point has no dimensions, only position

**A Line is one-dimensional**

A Plane is two dimensional (2D)

A Solid is three-dimensional (3D)