What is T9 in your mobile phone?

What is T9 in your mobile phone?

T9 dictionary is a general feature of any mobile phone. T9 actually stands for ‘Text on 9 keys’. It is a predictive text technology developed by Tegic Technologies. Similar software available is iTap, created by Motorola, and LetterWise, created by Eatoni. T9 makes it easier to type text messages on small mobile devices. The technology allows words to be entered by a single key press for each letter, as opposed to the approach used in the older generation of mobile phones in which several letters are associated with each key, and selecting one letter often requires multiple key presses.
The software combines the groups of letters found on each phone key with a fast-access dictionary of words. It looks up all the possible words corresponding to the sequence of key presses in the dictionary.As the predictive software gains familiarity with the words and phrases the user commonly uses, it speeds the process by offering the most frequently used words first and then lets the user access other choices with one or more presses of a predefined NEXT key.
The dictionary can be expanded by adding missing words, enabling software to recognize them in the future. After introducing a new word, the next time the user tries to produce that word T9 will add it to the predictive dictionary.
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