“When a carpenter wants to cut a half-dozen boards to the same length, he is unlikely to measure each one, mark it, and then carefully guide his saw along the line he has made on each board. Rather, he will make a jig
A jig reduces the degrees of freedom that are afforded by the environment. It stabilizes a process, and in doing so lightens the burden of care—on both memory and fine muscular control. The concept of a jig can be extended beyond its original context of manual fabrication. As David Kirsh points out in his classic and indispensable article “The Intelligent Use of Space,” jigging is something that expert practitioners do generally, if we allow that it is possible to jig one’s environment “informationally.”
Excerpt From: Matthew B. Crawford. “The World Beyond Your Head.” iBooks. https://itunes.apple.com/us/book/the-world-beyond-your-head/id923962482?mt=11