Patent ID: 7576662

Claim:
A keypad of a portable terminal including an array of a plurality of alpha-numeric key buttons for the input of alphabetic letters of the English language, comprising: a vowel input portion including a plurality of key buttons, to which vowels of the English alphabet showing high frequencies of use are allotted, and some consonants of the English alphabet are also allotted, the key buttons of the vowel input portion being grouped together; and a consonant input portion including the remaining key buttons of the keypad, to which the remaining consonants of the English alphabet are allotted, wherein the consonants and vowels of the English alphabet are classified into groups of two or more based on a similarity in geometrical shape thereof, and the resulting groups are allotted to the key buttons of both the consonant input portion and the vowel input portion, and wherein one consonant or vowel of the group allotted to each of the key buttons, having the simplest geometrical shape, is set to be a representative letter of the key button.