Consider 3 points on a line and say the line goes through a plane; they meet at a point.
Think about a sheet of paper being a plane and pretend your pencil is the line. The pencil can be on the paper and so these collinear points we considered would also be coplanar.
But you could also take the paper and stab the paper so the pencil only touches the paper at the hole it made (while still being in the paper). Not all the 3 points we considered on the line would be coplanar because they wouldn't all be touching the paper.
