1Customise trackpad gestures for pointing and clicking
Open System Preferences > Trackpad from the second row. Click on the first tab, ‘Point & Click’. If you’d rather tap your Mac’s trackpad than press down to click, check the first box. If you want to add a secondary click (a ≈- click action), check the next box down and choose one of the options from the drop-down menu.
The next option is very useful. Check it and you can tap any word in any document with three fingers to look it up in the Dictionary, Thesaurus and Wikipedia. Finally, to move windows by dragging with three fingers, check the bottom box.