LG GS200 Quick Reference Manual page 55

Entering Text
You can enter alphanumeric characters by using the phone's keypad.
Change the text input mode by pressing the # key.
T9 Mode
The T9 predictive text input mode lets you enter words easily with a
minimum number of key presses. As you press each key, the phone
begins to display the characters that it thinks you are typing based on
the built-in dictionary.
ABC Mode
This mode allows you to enter letters by pressing the key labeled with
the required letter once, twice, three or four times until the letter is
displayed.
123 Mode (Numbers Mode)
Type numbers using one keystroke per number.
Symbol Mode
The symbol mode enables you to enter various symbols or special
characters. To enter a symbol, select Options ➞ Insert Symbol. Use the
navigation and numeric keys to select the desired symbol and press the
OK key.