Apple co-founder Steve Wozniak said that he is a hacker to his core and loves to play pranks on friends and family.
Woz told Network World he had fun with light-hearted forays into hacking computer and telecommunications networks several decades ago.
He said that people with imagination in engineering are naturally drawn to the idea of finding ways to bypass security controls.
But Woz added that he never once hacked a computer for real and his break-ins were done in the spirit of exploration, never for profit or malice.
One prank involved some experimentation into a shared computer system where he left nine pages of Polish jokes.
Once he read an article about how tone signalling could be used to manipulate telephone networks to set up calls. Woz worked out the exact frequencies and tried them out on the telephone system. He used his skills to explore the network but did not steal or avoid paying bills.
He admitted he used to sneak into at least one eminent Stanford institution's lab every Sunday when it was supposed to be closed, to find electronics and science manuals.
Many of Woz's break-ins were combined with a prank. Once he guessed his stepson's password for the Macintosh and made the files he found hard to access. He and his wife teamed up on the kid to leave a folder marked "from Mom".