To use iPhone, you need:
A wireless service plan with a carrier that provides iPhone service in your area
A Mac or a PC with a USB 2.0 port and one of the following operating systems:
Mac OS X version 10.4.11 or later; version 10.5.7 or later is required for syncing Notes and for using iPhone as a modem
Windows XP Home or Professional with Service Pack 3 or later
Windows Vista Home Premium, Business, Enterprise, or Ultimate edition
Display resolution on your computer set to 1024 x 768 or higher
iTunes 8.2 or later, available at www.itunes.com/download (iTunes 9 or later required for certain features)
QuickTime 7.6.2 or later (for playing videos recorded by iPhone 3GS on your computer)
An iTunes Store account (for purchases from the iTunes Store or App Store)
An Internet connection for your computer (broadband recommended)