The Original Dune Series
The glossary of the novel Dune includes the following:
JIHAD, BUTLERIAN: (see also Great Revolt) — the crusade against computers, thinking machines, and conscious robots begun in 201 B.G. and concluded in 108 B.G. Its chief commandment remains in the O.C. Bible as "Thou shalt not make a machine in the likeness of a human mind."
In Dune Messiah (1969), the Tleilaxu Face Dancer Scytale notes that "From the days of the Butlerian Jihad when 'thinking machines' had been wiped from most of the universe, computers had inspired distrust."
Herbert refers to thinking machines and the Jihad several times in his later works in the Dune series, but does not give much detail on how he imagined either. In God Emperor of Dune (1981), Leto Atreides II indicates that the Jihad had been a semi-religious social upheaval initiated by humans who felt repulsed by how guided and controlled they had become by machines:
"The target of the Jihad was a machine-attitude as much as the machines," Leto said. "Humans had set those machines to usurp our sense of beauty, our necessary selfdom out of which we make living judgments. Naturally, the machines were destroyed."
Later in the same novel, Leto tests Siona Atreides, who experiences a vision of the future Leto is trying to prevent with his Golden Path:
He knew this experience, but could not change the smallest part of it. No ancestral presences would remain in her consciousness, but she would carry with her forever afterward the clear sights and sounds and smells. The seeking machines would be there, the smell of blood and entrails, the cowering humans in their burrows aware only that they could not escape . . . while all the time the mechanical movement approached, nearer and nearer and nearer ...louder...louder! Everywhere she searched, it would be the same. No escape anywhere.
Herbert's death in 1986 left this topic unexplored and open to speculation.
Read more about this topic: Thinking Machines (Dune)