It’s something we already take for granted: when we touch an icon on the screens of our electronic devices, we expect something to happen. And not just anything, either; we anticipate our gadgets to do exactly what we’d like it to do, when we want it done, and all at the touch of a fingertip. It was not too long ago that touchscreen technology was a source of wonder. Today, touchscreen technology is a given for many of the latest gizmos—from tablets to GPS units.

While most of us use this technology on a daily basis, most of us do not know how it works. How does a screen know what to do when we touch an icon? There are various types of touchscreen technologies but they all operate based on a similar idea.

Resistive touchscreens

Many touchscreens today operate on the resistive model. Resistive touchscreens are coated with a thin electrically conductive layer. Whenever you touch the screen, your fingertip causes the electrical current to change. This information is instantly sent to the device’s controller, which causes the unit to react to your touch. Resistive touchscreen technology is cheaper, and is the most frequent form of touchscreen used in products today. However, such touchscreens aren’t the most sensitive.

Surface wave touchscreen

Another popular type of touchscreen is the surface wave model. This kind of screen utilizes ultrasonic waves that pass over the touchscreen panel. When you touch the panel, you absorb a part of the wave. Again, this sends information to the device’s controller, which in turn tells the unit what you would like it to do.

Capacitive touchscreens

Devices that rely on capacitive touchscreens tend to have the sharpest image quality. Capacitive touchscreens are coated with a material that sends a continuous electrical current across the sensor. The good news is, the human body is also a form of electrical device. Which means that when you touch the screen you absorb some of the current. The device registers this disturbance, causing it to send information to its controller. The unit will then perform the action which you requested.

Fortunately, to enjoy touchscreen technology you don’t have to have a deep understanding of it. And you don’t have to be an engineer to realize this technology will become more popular, not less.