SAN FRANCISCO  Apple is one of the world’s coolest companies. But there is one cool-company trend it has rejected: chatting with the world through blogs and dropping tidbits of information about its inner workings.

Few companies, indeed, are more secretive than Apple, or as punitive to those who dare violate the company’s rules on keeping tight control over information. Employees have been fired for leaking news tidbits to outsiders, and the company has been known to spread disinformation about product plans to its own workers.

“They make everyone super, super paranoid about security,” said Mark Hamblin, who worked on the touch-screen technology for the iPhone and left Apple last year. “I have never seen anything else like it at another company.”

But even by Apple’s standards, its handling of news about the health of its chief executive and co-founder, Steven P. Jobs, who has battled pancreatic cancer and recently had a liver transplant while on a leave of absence, is unparalleled.