This work presents a subject which deals with man machine interfaces. Its objective is to study the data-processing impact of the integration of the Arabic language in mobile phones, in order to make an Arabic man machine interface. The correct display of Arabic characters is essential in a graphic interface, and because Arabic characters change their forms according to the position occupied in a word, it is necessary to make a contextual analysis on each word, to find the correct form of each character. The Arabic language has a different direction of writing compared to other languages...