Apple's Oct. 4 iPhone event is not only an important event on the technology calendar, but also for Apple itself as it is likely to break the tradition of Steve Jobs taking the center stage to unveil a new iPhone.

The so-called iPhone 5 is expected to come pre-loaded with iOS 5 and have bigger screen, a dual-core A5 processor, an 8MP camera and better antenna.

This would probably be the first time in Apple's history that Steve Jobs may be missing an iPhone event. Steve Jobs' extraordinary 35-year career at Apple has spanned world transformations that he has had no small role in creating.

Tim Cook, who succeeded Jobs as Apple CEO, is more likely to take the stage at Apple headquarters at Cupertino, where the tech geeks would get a glimpse of how new CEO Cook fares at Tuesday's major product launch.

Although a highly regarded executive, Cook is generally not known for pitching products. While Cook's operational excellence has been proven time and again, he will now need to prove with his iPhone 5 presentation that he can also fill Steve Jobs' role as an Apple's brand ambassador.

Meanwhile, the Oct. 4 event would mark a new era for Apple and its products, including iPhone, iPad and Macs.

But, there are speculations that Jobs would surprise everyone by attending the iPhone event and launch of the so-called iPhone 5 after Cook delivering the keynote speech at Tuesday's event. Others say Jobs' role could be limited to a pre-recorded video message.

Some argue that since Jobs has resigned as CEO should his presence required at the event. Moreover, other arguments say that Cook should preside the event as any efforts to pass on the presentation to others could undercut his new role and may give a feeling that Apple has not come out of Jobs' shadow.

Tim Cook may be the best man for Apple after Jobs, but Jobs is still irreplaceable as he is widely recognized as the driving force behind Apple's culture of innovation that took it from near collapse to become an industry leader and one of the most respected brands globally. Jobs was instrumental in the success of products like Mac, iPod, iPhone and iPad that frustrated competitors like Google and Microsoft.

Jobs, who co-founded Apple in 1976, was ousted by the board in 1985.  In Sept. 1997, the Cupertino, California-based company was 90 days away from bankruptcy and had incurred almost $2 billion in losses in only two years. The stock was trading at $5.48.

Since resuming the reigns of Apple in 1997, Jobs' eye for detail, and focus on sleek, easy-to-use products helped Apple distinguished itself from competition and made products like the iPad, iPhone and iPod as functional fashion statements. Under Jobs' leadership, Apple has become the world's second most valuable company after Exxon Mobil Corp. Its shares are now worth $376 apiece.

Jobs is also known for his dynamic presence at the Apple events. Jobs had the charisma and the showmanship that helped audience understand his vision. Even at the height of his illness, he came back from medical leave to unveil iPad 2 in March this year.

We've been working on this product for a while and I just didn't want to miss the day, Jobs said at the event.

Will Steve Jobs emerge again and do an encore, unveiling the latest iPhone? Only time will tell.