After months of speculation, Apple CEO Steve Jobs finally unveiled the company’s much-anticipated tablet, called iPad. “It’s like holding the Internet in your hands,” he told a rapt audience in San Francisco.

So what is iPad, and how is it different from other devices out there?

The tablet features a 9.5-inch, LED-backlit screen. It weighs in at 1.5 pounds and is only half an inch thick. Yet, from day one, it offers access to more than 140,000 apps that executives say have been “completely redesigned for iPad.” And iPhone apps already downloaded should work as well. It can be used both vertically and in “portrait” mode and boasts a “full-page view” of websites, says Jobs.

Part e-reader—with a link to the company’s iBooks storefront—part email client, part Web browser, and part movie platform, Apple is betting that customers who’ve already bought into the iPhone lifestyle will add iPad to their arsenal of gadgets. Much of the navigation mimics that of the phone, featuring a reputedly more sensitive multitouch screen and a QWERTY keyboard that rivals the size of a laptop’s for ease of typing.

Past Apple devices have been criticized as not having a long enough battery life, especially when watching movies. Will that be a problem for iPad? Until customers can play with the product, the company is promising a 10-hour battery output. The device runs on a 1GHz custom-designed Apple A4 chip. The regular iPad comes with built-in 802.11n, to locate and connect to the fastest WiFi networks in the area. The upcoming 3G models feature data speeds up to 7.2 Mbps, according to the company.

Most analysts expect the iPad to give Amazon’s bestselling Kindle some heated competition in the way that Barnes & Noble’s Nook has not yet been able to do. But the question remains: In these economic times, will customers spend between $499 for the 16 GB model ($629 for the 3G-enabled version) to upwards of $699 for the 64 GB device, plus the $130 for wireless 3G and the $29.99 monthly fees of an AT&T contract?

That remains to be seen. But shares of the company rose after Jobs announced the new device and also gave carrier AT&T a boost on the lower-than-expected pricing. Analysts had previously thought the device will run from $600 up to a potential $1,000.

Apple designers are touting this new product as a whole new class of devices, way surpassing the netbook’s “cheap” model, as Jobs said. Of course, accessories are available, starting with a stand-alone keyboard and a carrying case. But it’s the apps that Scott Forstall, senior vice president for iPhone software is calling the “gold mine,” for future developers. With 140,000 already available, is there room for many more? Yes, said Forstall, who added that the iPad SDK will have even more apps specifically designed just for it.

Ready to go out and buy yours today? You’ll have to wait. A link on Apple’s website lets customers sign up to be notified when iPad will be available in their area. For most, WiFi models will ship in late March and 3G versions will be ready in April.