segment | the part of a line containing two endpoints and all points between them. |
ray | the part of the line consisting of one endpoint and all the points of the line on the one side of the endpoint. |
opposite rays | two collinear rays with the same endpoint. |
parallel lines | coplanar lines that do not intersect. |
skew lines | noncoplanar lines that do not intersect. |
parallel planes | planes that do not intersect. |
congruent segments | segments with the same length |
midpoint | the point that divides the segment into 2 congruent segments |
coordinate | the number value assigned to a point. |