(AP) -- There was no makeshift memorial or candlelight vigil for Steve Jobs at the Apple Store in downtown Chicago. The news of his death, and then the tributes and condolences, were in news alerts, tweets and messages pulsing through the gadgets inside.
Peter O'Reilly knew something was wrong as shoppers perused iPhones, iPads and laptop computers Wednesday evening, and an employee with a somber look started to cry. She told him the news.
"I can't imagine a world without Apple products," said O'Reilly, a 33-year-old electrician visiting from Ireland.
Marks of respect soon flowed from around the world. "iSad" was a trending topic on Twitter. Mac Users Group Mexico released a statement that concluded, "Let's breathe deeply and say VIVA STEVE JOBS!"
There were more traditional tributes closer to Silicon Valley. People placed flowers and scrawled chalk messages in front of the gates of Jobs' Palo Alto home, where family and friends gathered. Someone wrote "Thank you Steve" in lipstick on the window of an Apple Store in Santa Monica.
At the San Francisco Apple Store in Union Square, a crowd started forming. A few dabbed their eyes. Others huddled in small groups around their iPhones reading the details of Jobs' passing.
Scott Robbins, 34, a barber from San Francisco and an Apple fan for nearly 20 years, said he came as soon as he heard the news.
"To some people, this is like Elvis Presley or John Lennon - it's a change in our times," Robbins said. "It's the end of an era, of what we've known Apple to be. It's like the end of the innovators."
Robbins said Jobs' influence extended beyond the iPhone he now carries and the Mac products he has faithfully bought for years. He was a symbol of the technology revolution who opened the eyes of a generation to the possibilities of the digital computing.
But the store wasn't consumed by sadness. Inside, peppy music played and customers watched YouTube videos on iPhones. That they were consuming technology in ways that would have been unimaginable without Jobs may have been lost on many of them.
In China, one of the company's fastest growing markets, Henry Men Youngfan said he was shocked by the news that his hero had died.
The 27-year-old doctoral student in Beijing bought his first Apple product in 2006 and traveled by train to Hong Kong in September just to attend the opening of the company's first store there.
When he entered graduate school at Peking University's college of engineering, Men said, "My teachers asked me what kind of person I wanted to be and I told them I wanted to be like Steve."
Li Zilong, who was listening to his iPod in front of a Beijing Apple store, worried that Apple's innovation died along with its co-founder.
"Jobs was a legendary figure; every company needs a spiritual leader," said the 20-year-old university student. "Without Jobs, I don't know if Apple can give us more classic products, like the iPhone 4."
Competitors who watched as Apple's sales - and its stock price - took off over the past decade posted messages of admiration:
"Steve Jobs was a great visionary and a respected competitor," said Mike Lazaridis and Jim Balsillie, co-CEOs of Blackberry-maker Research in Motion.
"Today the world lost a visionary leader, the technology industry lost an iconic legend and I lost a friend and fellow founder," said Dell Inc. founder and CEO Michael Dell.
"For those of us lucky enough to get to work with Steve, it's been an insanely great honor. I will miss Steve immensely," said Microsoft co-founder Bill Gates.
At an Apple Store in New York City, where a small collection of flowers and candles had started to form, Jacqueline Thuener-Rego, said Jobs has helped change how people think about their relationship with technology.
"You don't think of it as technology, you think of it as memories, experiences," the 28-year-old actress from Brooklyn said. "It's as integrated into your life as a cup of coffee. The technology has become the human experience."
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