The mathematical terms that cannot be defined for all
cases in a system of geometry are the parallel lines and midpoint of a line
segment. A line is an infinite series of points in a row and it does not occupy
any space. They are also called one dimensional since the direction is in one
dimension. A point has a location but no specific size. It can describe a
location but you can never determine its actual size. Imagine the point at the
end of the previous sentence. And then imagine it getting smaller and smaller
until it disappears. We can only use a dot to represent the point.
