View source for II. Technology should inform and create calm

==Introduction==
A technology informs when it changes what a person knows. It alarms when it changes what a person is doing. The difference is not volume or urgency but placement. Information that arrives where a person is already looking costs nothing to receive. Information that arrives by interrupting costs the task in progress.
 
Calm technology delivers status through the channel a person is already using, at the moment the status changes, and at a level matched to the importance of the change. A device that reports everything at the same intensity teaches people to ignore all of it.
 
* A car's temperature gauge sits in view for the length of a drive and is read in a glance.
* A cooking timer stays silent for the entire cooking period and speaks once.
* A watch face reports the time continuously without ever requesting attention.
 
===The Whistling Kettle===
A whistling kettle produces one signal, at one moment, for one reason. Water reaching a boil moves steam through a fitted opening and the kettle whistles. Nothing precedes the whistle. No progress bar, no percentage, no intermediate chime at seventy degrees.
 
The signal is also self-limiting. The whistle continues until the kettle is removed from the heat, which means the alert cannot be dismissed without resolving the condition that produced it. A person can leave the room and still be informed, because the sound carries and because it has no competition from other sounds the kettle makes.
 
A kettle that informs does not need to:
*Report its progress toward boiling
*Confirm that it has been filled
*Announce that it has been turned on
*Distinguish between levels of urgency
 
Mark Weiser and John Seely Brown described this quality in "Designing Calm Technology" (Xerox PARC, 1995) using Natalie Jeremijenko's Dangling String, a plastic cord attached to a motor wired to an Ethernet cable. Network traffic made the string twitch. Heavy traffic made it whirl. Nobody had to read it, and nobody had to dismiss it.
 
Just as a kettle stays silent until the water boils, well-designed technology reports the state that matters at the moment it changes and stays quiet the rest of the time.
 
==Categories==
[[Calm Technology]]