Parallel lines are two lines that never intersect and have the same slope, while perpendicular lines are two lines that intersect at a 90-degree angle and have slopes that are negative reciprocals of each other. The difference between the two is that parallel lines never intersect, while perpendicular lines do.
Parallel lines are two or more lines in a plane that never intersect, while perpendicular lines are two lines that intersect at a right angle. The difference between the two is that parallel lines never cross each other, whereas perpendicular lines do cross but at a 90-degree angle.
