Explaining how a touchscreen works with a sausage (video)

During South Korea's brutal winter of 2010, frustrated glove-wearing smartphone users learned that they could use sausages instead of their finger. This hack became so popular that one sausage manufacturer reported a 40% spike in sales, as BBC's "The Secret Genius of Modern Life" reports.

The science behind this hack reveals how our everyday touchscreens work. Hidden beneath your phone's glass is an invisible mesh of indium tin oxide — a material that stores and conducts electricity. This creates an electrical field that your finger disrupts when it touches the screen.

"This is not me pushing these balls around," explains the host, using statically-charged polystyrene balls to demonstrate how the electrical field responds to touch. "It's the interaction between the stored charges of these two conductors, your finger and the grid inside your phone, that makes this touchscreen work."

The key ingredient that makes fingers, sausages, and even pickles work as styluses is salt water. "Like the pickle, we are mostly made from salty water, and that's what allows us to store charge and conduct electricity," the host explains. Regular gloves and metal utensils fail because they can't conduct electricity the same way.