How do touchscreens work?

How does a touchscreen work? Why can you text with your finger, but not with a q-tip? The physics of smartphones is a complicated and amazing mixture of engineering, physics, electronics and computer science. Topics: Capacitive touch screen Binary language Unicode Subscribe to Physics Girl for more fun physics! https://www.youtube.com/subscription_center?add_user=physicswoman Help us translate our videos! http://www.youtube.com/timedtext_cs_panel?c=UC7DdEm33SyaTDtWYGO2CwdA&tab=2 Creator: Dianna Cowern Research/Writer: Sophia Chen Editor: Jabril Ashe & Dianna Cowern Animations: Kyle Norby Videography: Cathy Cowern Thanks to Dan Walsh and Marcel Stieber http://physicsgirl.org/ http://twitter.com/thephysicsgirl http://facebook.com/thephysicsgirl http://instagram.com/thephysicsgirl