Do you know why the ‘F’ and ‘J’ keys have raised ridges on them on a Keyboard? ‘5’ numbered key in Numeric keypad also has a ridge on it. Many think that it is a production defect. Check out the actual reason behind the ridges on ‘F’, ‘J’ and ‘5’ keys.
The main reason for these bumps or ridges placed on ‘F’, ’J’ and ‘5’ keys are that they indicate the exact position of fingers while typing.
If you are typing speed without looking at the keyboard, these ridges help you find the position of your fingers. Both your index fingers had to be placed on ‘F’ and ‘G’ keys to know the position of keys on the keyboard.
The exact position of your fingers must be as follows:
Positioning your left index finger on the ‘F’ key and your right index finger on the ‘J’ key leaving the other three fingers of your left hand to rest on the ‘D’, ‘S’, and ‘A’ keys and your right hand to rest on the ‘K’, ‘L’, and ‘:/;’ (colon) keys. Your both thumb fingers must rest on the space bar.
These improvements came to keyboards as a result of a patent filed by June E. Botich in 2002 and all keyboards manufactured after that contains these ridges.