What is non-coplanar lines?
yes, two lines can be coplanar.
No, not always. Skew lines are never coplanar, but parallel lines are.
No. If two lines intersect, then they're definitely coplanar.
Parallel lines in Euclidean space are always coplanar.
What is non-coplanar lines?
coplanar lines are lines lying on the same plan.
No, non-coplanar lines are not skew. Skew lines are non-coplanar lines that do not intersect and are not parallel. Non-coplanar lines are simply lines that do not lie in the same plane. Skew lines, on the other hand, are non-coplanar and not parallel, making them a specific subset of non-coplanar lines.
Perpendicular
yes, two lines can be coplanar.
Coplanar lines that do not intersect are called parallel lines.
No, not always. Skew lines are never coplanar, but parallel lines are.
are two lines that are not parallel, coplanar, and do not intersect
No. If two lines intersect, then they're definitely coplanar.
Non-coplanar, by a strange coincidence!
they are skew lines.
Parallel lines in Euclidean space are always coplanar.