In April 1975, in a bar in the Bonny Doon area of Santa Cruz County, California, Gary Dahl listened to his friends complain about their pets; this gave him the idea for the perfect "pet": a rock. A rock would not need to be fed, walked, bathed, or groomed, and it would not die, become sick, or be disobedient. Dahl said that they were to be the perfect pets and joked about it with his friends. He took his idea seriously, however, and drafted an "instruction manual" for a pet rock. The 32 page manual was full of puns and gags that referred to the rock as an actual pet.

The fad only lasted from the Christmas shopping season of 1975 until the next spring and quickly faded away.

Dahl continued to work in his advertising business; however, for years afterward, Dahl was hounded by "a bunch of wackos" approaching him for assistance with a multitude of bad ideas, lawsuits and threats. Dahl said in 1988, "Sometimes I look back and wonder if my life wouldn't have been simpler if I hadn't done it."

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