The two parts of any text message are the message itself and the mobile phone number to which you want to send that message. You can type a phone number or tap a phone number saved in your Contacts program. Each time you send or receive a text message from the same person (identified by his or her mobile phone number), your iPhone stores that message in a list.
To write and send a text message, do this:
From the Home screen, tap Messages. The Messages screen appears, listing all your text messaging conversations, as shown in Figure 16-1. (The number of unread text messages appears in parentheses next to the Messages heading.)
Figure 16-1. The Messages screen displays all your current text message conversations.
Tap the New Message ...