Here’s a neat trick: anyone who uses chat programs like AIM or MSN knows you can put smilies in your messages. If you type 🙂 it ends up being changed into a round yellow smilie face. My wife pointed out to me that you could do the same on an iPhone without installing a separate app for it. She always looks to me to answer her computer questions, so she was quite surprised that she was able to teach me something.
Your iPhone supports multiple language keyboards, which can be activated from Settings > General > Keyboard > International Keyboards. Tap Add New Keyboard, then scroll down the list until you find Emoji. Select it, and it now shows up in your list of keyboards.
Now, when you’re composing a message (in Messages, Mail, or any app that uses the virtual keyboard for input) you will see a globe icon on the lower left next to the numeric key. Tap this to bring up a list of emoticons (the “geek” name for smilies). In addition to various faces, you can also put pictures of fish, flowers, holiday icons, zodiac signs, etc. To go back to English, tap the globe button again.