The variants of keyboard used with computers

Home keyboard with iphone dock

Promini wireless keyboard with track pad

The keyboard is one of the most and first peripherals to be used with computers. If you have a desktop computer, there's a good chance you've been using the basic keyboard that came with it and may be need of an upgrade. A standard keyboard has 100 keys, each of which sends a different signal to the CPU. If you're a laptop or a notebook user, on the other hand, you may simply be sick of typing with your nose so close to your screen.
Whatever your reason for wanting a new keyboard, there are a few things you should consider before plunking down your money. First and foremost, decide what tasks you'll be primarily using the keyboard for. Of course, you may be a combination of some, or even all, of these types, so you should prioritize the features that are most important to you before you start searching.
Ergonomically correct keyboards:
Many variations have been made on the standard keyboard, primarly for the sake of comfort and the reduction of repetitive stress injuries. People who type a great deal is susceptible to arm and hand fatigue and strain. New, ergonomically correct keyboards can help reduce those problems.
These are designed to help the users hands stay positioned correctly, reducing bending and strain. An ergonomic keyboard maybe curved in some way, or it may be in to two separate sections so the user can place them most comfortably on the desktop. 
Gamer
Gamers are a specific breed unto themselves, and they typically require or desire keyboard features that are wasted on the rest of us. Things like integrated LCDs, programmable keys, backlighting and changeable number pads can give PC gamers increased benefits and enhance the gaming experiences.
If you're a gamer, look for keyboards that are specially labeled as gaming keyboards. You can expect to pay a higher price for these features, but most serious gamers will tell you they're worth the cost.