The "Timebar" is the area above the Time Track Panel, the Graphs Panel and also at the bottom of the Canvas Window.
It indicates time as a frame ruler and you click and drag within it to scrub your timeline.
It display the keyframes you have set (not in the Graphs Panel), their activation state and the selected one.
Three keyframes with three different states : Normal, Selected and Deactivated
You can adjust the Time of the keyframe by drag and drop or the Length of the keyframe by holding Alt key when releasing the mouse button.
The timeline at the bottom of the Canvas Window only appears when you have defined a non-zero duration in the Canvas Properties Dialog.