T9
From MobileRead
T9 is a text entry system using the 9 number keys - T9 stands for Text 9. It is most often used with cell-phones.
[edit] Overview
Text entry using a numeric keyboard is well known to cell-phone users. Typically 3 letters are assigned to each number and you tap once for the first letter, twice for the second letter and three times for the third.
The idea behind T9 is that you will only need to tap a key once to get letters for a word. The secret is that it uses a dictionary to figure out which of the 3 (or 4) letters is correct. As you type it will redo earlier letters if needed to make a word. If you need a number then tap and hold on the key until the number appears on the screen.
Of course, 9 keys are not quite enough in practice. You need a NEXT button to select from available choices if it picks the wrong word, a back button to fix an incorrect entry, and a space button to tell it the word is done.
The number 1 is used to enter punctuation. A learn button allows you to add new words to the dictionary using traditional key entry or just to make a word it doesn't know.
[edit] mapping
- 1 punctuation
- 2 ABC
- 3 DEF
- 4 GHI
- 5 JKL
- 6 MNO
- 7 PQRS
- 8 TUV
- 9 WXYZ
- * caps/caps lock
- # space
