What are the explanations of skew lines?

Answer 1

In plane geometry, two straight lines are either parallel (including coincident) or they meet at a point. In three dimensions, however, there is another option: the lines could be skew. These are lines that are not parallel but which do not intersect either. One way to visualise this is to place yourself in a cuboid room facing one wall. Consider the vertical line where the wall in front of you meets the wall to your left. And then consider the line where the floor meets the wall to your right. These two lines are not parallel but they will never meet. These are skew lines.