The bumps placed on the F and J letters on the keyboards serve to help the users locate the exact keys more easily without looking at the keyboard. The reason why there are bumps only on these two keys is the fact that they signify the ideal hand position during typing. By placing the two index fingers on these two keys, the left hand covers A, S, D, and F, while the right one covers J, K, L, and the semicolon. The thumbs are placed onto the Space button. The keyboard bumps were introduced by June E. Botich as a way to increase the speed and preciseness of the keyboard users.
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