The object starts out going very fast in the positive direction. It then gradually slows to a halt, then gradually speeds up in the negative direction.
Oh, by the way, the graph is a movie. Go watch it now & return here. (Right click to bring up its play menu.)
Be careful interpreting this animation. This is not a 2-D plot of the motion of the orange ball flying through the air. That is, it's not a plot of y vs. x. It's position vs. time.
The red ball keeps track of the passing time.
The orange ball just shows the current point on the graph, not the position.
The green ball indicates the position of the object at each instant. This ball shows the actual motion we're talking about.