What you have observed is a stationary wave on the long spring. There are points along the spring that remain (almost) motionless while points on either side are oscillating with the greatest amplitude. The points that do not move are called the nodes and the points where the spring oscillates with maximum amplitude are called the antinodes. At the same time, it is clear that the wave profile is not travelling along the length of the spring. Hence, we call it a stationary wave or a standing wave.
We normally represent a stationary wave by drawing the shape of the spring in its two extreme positions (Figure 14.4). The spring appears as a series of loops, separated by nodes. In this diagram, point A is moving downwards. At the same time, point B in the next loop is moving upwards. The phase difference between points A and B is ${180^ \circ }$. Hence, the sections of spring in adjacent loops are always moving in antiphase; they are half a cycle out of phase with one another.