Why do touchscreens work with fingers?
Show answer & explanation
Answer: Fingers conduct electricity
Pressure triggers touch detection — Wrong. Old resistive screens used pressure, but modern capacitive screens detect electrical conductivity from your conductive finger.
Fingers conduct electricity ✓ — Correct! Most modern touchscreens are capacitive—they store electrical charge. Human bodies conduct electricity. When your finger touches the screen, it draws charge from that spot, changing the electrostatic field. Sensors detect this change and locate the touch. That's why styluses need conductive tips and gloves don't work (unless they're conductive)!
Skin oils create connection — Wrong. Oils don't affect capacitive screens. They detect electrical properties of your finger—your body's conductivity disrupts the screen's electrostatic field.
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