Editing Touch-sensitive surface (section)

== Technology ==
The most common touch-sensitive technology is '''capacitive''' sensing. Capacitive sensors depend on the electrical properties of the user's fingertips.

Capacitive touch sensors have the drawback that they are unable to sense gloved hands or traditional plastic styli, and this can especially be a problem for mobile devices when used in cold weather.
The market has adapted to this, though. These days, there are several styli available with capacitative properties. There are also special "smartphone gloves" with capacitative fingertips. Previous to these products, there have been reports of people carrying uncooked sausages in their pockets for use as styli in cold weather<ref>[http://www.tomsguide.com/us/South-Korea-Sausages-iPhone-Stylus,news-5815.html tomsguide.com article on sausages used as a stylus]</ref>.

Capacitive sensor technology has the advantage that multiple simultaneous points can be detected. This has led to the introduction of multi-touch trackpads and displays.

Prior to touchscreens, capacitive sensing was used in [[Switch terminology|capacitive keyboard switches]]. [[Topre switch]]es continue to use this method today.

Some other sensing technologies are:

;Resistive
:The surface needs to be pressed down. Common on older pen devices and on cheaper touch-tablets. Resistive panels can be prone to jitter, as seen on Psion's range of palmtops.
;Light beams
:Used by NeoNode devices (the ones that have prior art on slide-to-unlock).
;Gyro sensor
:Used primarily for [[touch screen]]s, these sense when and how the screen is nudged when pressed (very unusual and primitive).

Touch sensors often have relatively low resolution.
Touch-points on a screen should therefore not be interpreted as a point but as a circle or ellipse.