Another we can visualize motion, particularly in one dimension, is by graphing the position, velocity, or acceleration as a function of time. Time is always on the horizontal axis in such graphs.
To make a position graph we need to define an origin (the point which we are calling "0") and a direction we're calling "positive" (often to the right, by convention.) The axis is usually labelled $x$ if the motion is horizontal and $y$ if it is vertical, although that's also a matter of convention: for an object moving along a diagonal, for instance, we could use either label.
The motion diagram of an object that moves to the left at a constant speed. The origin is chosen in the middle of this line.
The corresponding graph for this object. The dots are not essential to the graph, but are useful for constructing the graph from the motion diagram: for each dot on the motion diagram, place a dot at the same value of $x$ and $t$. Constant velocity corresponds to a linear position graph.
The motion diagram of a block oscillating on a spring: it moves to the left, stops, and goes back to the right. (I've shifted some of the dots down so they don't overlap.)
This is the corresponding graph. The minimum or maximum of a position graph is called a turning point, and occurs when the object changes direction.
