At this time the sounds Hin and others may be made, alternately or optionally, according to habit. When the man, making the sound Phât, strikes the woman on the head, with the fingers of his hand a little contracted, it is called Prasritaka, which means striking with the fingers of the hand a little contracted. In this case the appropriate sounds are the cooing sound, the sound Phât and the sound Phut in the interior of the mouth, and at the end of congress the sighing and weeping sounds. The sound Phât is an imitation of the sound of a bamboo being split, while the sound Phut is like the sound made by something falling into water.
In a 1981 article entitled "The truth about Unix: The user interface is horrid "  published in Datamation , Don Norman criticized the design philosophy of Unix for its lack of concern for the user interface. Writing from his background in cognitive science and from the perspective of the then-current philosophy of cognitive engineering ,  , he focused on how end users comprehend and form a personal cognitive model of systems--or, in the case of Unix, fail to understand, with the result that disastrous mistakes (such as losing an hour's worth of work) are all too easy.