angle
A figure formed by two rays with a common endpoint
perpendicular lines
Two lines that intersect to form right angles
parallel lines
lines in the same plane that never intersect
line segment
a part of a line that has two endpoints
ray
a part of a line that starts at an endpoint and extends forever in one direction
circle
A round plane figure whose boundary consists of points equidistant from the center
skew lines
Lines that do not intersect and are not coplanar