The iPhone is a line of smartphones designed and marketed by Apple Inc. that use Apple's iOS mobile operating system. The first-generation iPhone was announced by then-Apple CEO Steve Jobs on January 9, 2007. Since then, Apple has annually released new iPhone models and iOS updates.

The iPhone is one of the two largest smartphone platforms in the world alongside Android, forming a large part of the luxury market. The iPhone has generated large profits for Apple, making it one of the world's most valuable publicly traded companies. The first-generation iPhone was described as "revolutionary" and a "game-changer" for the mobile phone industry and subsequent models have also garnered praise.

Development of what was to become the iPhone began in 2004, when Apple started to gather a team of 1,000 employees led by hardware engineer Tony Fadell, software engineer Scott Forstall and design engineer Sir Jonathan Ive to work on the highly confidential "Project Purple."

According to Steve Jobs, the "i" word in "iMac" (and therefore "iPod", "iPhone" and "iPad") stands for internet, individual, instruct, inform, and inspire.

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