t9 is a predictive text
entry system that is optimize
d for use with cellular phone keypad
s, developed by Tegic Communications
When entering letters on a conventional phone keypad, you must somehow differentiate between which of the 3 or more letters that you want to use. For example, pressing the 5-key could mean you wanted a J, K, or L. Normally, you must either press the same key multiple times (twice to get a K, five times to get a K in the opposite case, seven times to actually just get the number 5), or you press an alternate key, like the * and # keys to select the left or right letter. So to type the word IF, you must usually type 444333 or 4#3#.
The t9 system appears to take the numbers, parse them out for all combinations, then match them against a dictionary. For example, to type the word "IF", you type:
You could mean nine different two letter combinations:
, and IF
. By matching with a dictionary, you can see that only a couple of these make sense. 'He
' and 'if
' are the most likely, and it chooses one. If you want another spelling, you can then choose a different interpretation
, much like the Microsoft IME
that comes with Windows
for entering Japanese
and Chineese Kanji
characters. You can also add
words to its dictionary
, to make words quicker to use next time you use them.
It is damn useful.