Mainly through [Settings] -> [Touchpad] to view and learn the use of various gestures
General Universal Gestures
Left mouse button function: click with one finger;
right mouse button function: click with two fingers;
scroll screen function: two-finger drag;
drag window: drag the pointer to the top of the window, then three-finger drag;
show desktop: four Separate your fingers;
open Launchpad: pinch with four fingers;
activate Missing Control: push up with four fingers;
switch desktops or full-screen applications: swipe left and right with four fingers;
display all windows of the current application: slide down with four fingers;
in Missing Control Zoom in on all windows of a single app: Point the pointer to the app, then swipe up with two fingers;
Gestures in Safari, Chrome and Firefox browsers
Zoom in on web content or text: pinch open with two fingers;
zoom out on web content or text: pinch in with two fingers;
back (previous page): swipe left with two fingers;
forward (next page): swipe left with two fingers;
look up a dictionary: in the text Or three-finger double-tap on a word (Safari only);
Smart Zoom: Two-finger double-tap on a webpage (Safari only);
Gestures in Quick Look
Enter full-screen mode: pinch with two fingers;
exit full-screen mode: pinch with two fingers;
Gestures in the preview app
To zoom in: pinch with two fingers;
to zoom out: pinch with two fingers;