Have you ever tried to scroll down in a Web page and selected a link instead—with the result that you now have to tap the Back icon and wait for the page to reload? If you have experienced this, or any similar annoyance, then this section is for you.
The main way you interact with an iPhone is by touching the screen. The exact way in which you touch the screen, called a gesture, determine which action is taken.
Here are the basics that you should know:
Tap: Tap any active area of the touchscreen and the relevant action is taken. For example, tap any application icon on the Home screen to open that application.
Double-tap: A double-tap (tapping twice quickly) has a special effect ...