What exactly is the original iPad? What are the differences between iPad configurations? Is it an iPod? Is it a Mac?

Please note that this Q&A specifically refers to the original iPad, although much of the general information is applicable to the current iPad 2 as well. You also may be interested in reading "What are the differences between the iPad 2 models? Which should I buy?"

In basic terms, the iPad is a tablet or "slate" computer. Apple formally declares that it is a "magical and revolutionary" device for "browsing the web, reading and sending email, enjoying photos, watching videos, listening to music, playing games, reading e-books and more."

Photo Credit: Apple, Inc.

Apple has designed the iPad to occupy a new product category between the iPod and the Mac, and consequently, it is really neither an iPod nor a Mac.

However, it does run a version of the same operating system as the iPod touch and iPhone (iPhone OS 3.2) and it is compatible with the vast majority of applications written for the iPhone and iPod touch as well, so it is not unreasonable to consider it a member of the iPhone/iPod touch "family" of products.

It does not run Mac OS X or Mac OS X applications, so it is not Mac, although the iPhone OS is derived from Mac OS X.

Photo Credit: Apple, Inc.

Like an iPod or iPhone, the iPad also can be synchronized with a Mac or Windows PC via the standard USB-based 30-pin iPod connector port, but it can be used like a basic computer with an external keyboard dock accessory or the Bluetooth-equipped Apple Wireless Keyboard as well (either US$69).

When combined with the iWork software Pages, the external keyboard capability makes it possible to comfortably compose full documents on the iPad, which can then be saved in Pages, Word, or PDF format and transferred to a computer for printing (or more directly from the iPad using third-party software). Spreadsheets and presentations, likewise, can be prepared with versions of the Numbers and Keynote applications from the iWork suite and saved in either native formats or in Excel or PowerPoint, respectively. Each iWork application is available for US$9.99 each.

There are six configurations of the iPad, which vary by capacity -- 16 GB, 32, GB, or 64 GB -- connectivity -- either 802.11n Wi-Fi or 802.11n Wi-Fi, 3G, and A-GPS -- and price.

All iPad configurations have a 9.7-inch (1024x768, 132 ppi) multitouch "glossy" LED-backlit IPS display, an accelerometer, ambient light sensor, digital compass, stereo speakers and a built-in mic packed in a 0.5 inch thick, 1.5 or 1.6 pound glass and aluminum case. All are powered by a custom ARM-based 1 GHz Apple A4 "system on a chip" and have an estimated 10 hours of battery life "surfing the web on Wi-Fi, watching video, or listening to music." Battery life while using the Internet over 3G is an estimated 9 hours.

As a minor detail, iPad configurations only with Wi-Fi have a solid aluminum back whereas configurations with Wi-Fi, 3G, and A-GPS have a plastic area on the top rear of the device for the 3G antenna. Wi-Fi only models are assigned model number A1219 and Wi-Fi, 3G, A-GPS models use model number A1337.

Photo Credit: Apple, Inc. (Left -- Wi-Fi, Right -- Wi-Fi, 3G, A-GPS)

An odd point that is worth mentioning is that the iPad does not ship with Apple's trademark white earbuds. In fact, it does not ship with any earbuds at all.

The differences between configurations -- capacity, connectivity, and price -- are charted below:

For models equipped with 3G connectivity, 3G data plans are available without a contract for US$14.99/month with a 250 MB data transfer limit and US$29.99/month for unlimited use via AT&T Wireless in the US.

For an excellent run down of the capabilities of the iPad in real-world use, you may also enjoy this hands-on video review from PC Magazine: