Traditional PCs are fading in popularity. The rise of tablets and smartphones has created an alternative to the once-dominant PC, and consumers aren't buying nearly as many as they once did. Yet you can't use a tablet for everything -- in many ways, PCs remain as valuable as ever before.

If you're in the market for a new laptop, you still have plenty to choose from -- so many in fact, that it's downright confusing. In this laptop buying guide, I'll lay out the differences between the different platforms and recommend a few different models.

Windows machines
Most laptops on the market are powered by Microsoft's (MSFT 1.65%) operating system. The majority on sale sport Windows 8, but you can still find plenty of Windows 7 machines if you prefer the traditional interface. With Windows laptops you have the most variety: Prices range from less than $300 to several thousand dollars, and screen sizes run from 10 to more than 17 inches. There are dozens of different manufacturers, with the top brands including Lenovo, Acer, Asus, Dell, Hewlett-Packard, Sony, and Toshiba.

If you're willing to get a Windows 8 machine, the touch-based interfaces open up another realm of customization entirely. There are a growing number of hybrid devices, with a number of different form-factors.

With so much variety, the best laptops will be the ones best suited to their owners' needs. Ideally, lighter, thinner laptops are preferable -- but you need something powerful enough to run your favorite applications and cheap enough to suit your budget. There are so many machines to pick from, but here are a few that stand out.

  • The hybrids: Asus Transfomer Book T100TA and Microsoft's Surface Pro 2

    Asus' Transfomer Book is a capable detachable for less than $500; Microsoft's Surface Pro 2 packs laptop power in the body of a tablet. But the Transfomer Book is relatively small (just about 10 inches) and the Surface Pro 2 is expensive (starting at $899).
  • Ultra portable: Lenovo ThinkPad X240 and Acer Aspire S7-392

    Lenovo's ThinkPad X240 has unmatched battery life, able to last for more than 20 hours without a charge; Acer's Aspire S7-392 is one of the all-around best Ultrabooks on the market. But the ThinkPad X240 has a low-resolution screen, and the Aspire S7 has a weaker battery and high asking price (starting at over $1,000).

  • Big and beefy: Lenovo IdeaPad Y510p and Alienware 17

    Both the Lenovo IdeaPad Y510p and the Alienware 17 are great laptops for gamers, or anyone who needs a powerful laptop capable of running demanding programs. The Alienware 17 sports fantastic specs but is particularly expensive (starting at $1,499), while the IdeaPad Y510p isn't as powerful but is far more economical (starting at $799).

  • Budget friendly: Dell Inspiron 17-3721 and Acer Aspire V5-131

    Dell's Inspiron 17 offers a 17-inch screen and decent specs for less than $500, while Acer's Aspire V5-131 is capable Windows machine with a starting price under $350. But neither offers a touchscreen, and the Aspire V5-131 is small, with just an 11.6-inch screen.

MacBooks
Apple's (AAPL 0.64%) MacBooks are widely praised, and consistently dominate rankings of the top laptops available. By default, they run Mac OS X, which is known to be extraordinarily stable and unlikely to fall prey to viruses or malware. However, Mac OS X is limited in terms of the software it can run -- not every game or business application is available for OS X. Still, if you need Windows, you can install it on your Mac by purchasing a Windows installation disc and using Boot Camp.

The biggest hurdle to Mac ownership is the price -- the cheapest Apple-made laptop is the 11-inch iPad Air, starting at $999, while the more powerful, 15-inch MacBooks run well over $2,000. But if you want unprecedented build quality and the stable computing environment OS X allows, it's hard to beat a Mac. Macs have a reputation for longevity -- there isn't much evidence to support this, but if you do run into any technical problems, you can just take it to your nearest Apple store and get it fixed.

The MacBook Air is good enough to handle most tasks, and is extremely portable. The bigger MacBook Pro gives you more power if you need it and comes with the option of a higher-resolution screen.

Chromebooks
Standing on the complete opposite side of the spectrum is the growing number of lightweight laptops that run Google's (GOOGL 1.27%) Chrome OS. Unlike MacBooks, they're extraordinarily cheap (most retail for less than $300) but obviously not very capable. In fact, they're downright limited.

That isn't to say that they're slow or buggy -- quite the opposite in fact. It's just that Chromebooks depend almost entirely on the Internet to function. There are some offline-capable apps, like Google's basic word processor and spreadsheet application, but for the most part, they serve as gateways to the Internet.

If you spend most of your time in the browser -- checking email, surfing the Web, browsing Facebook, watching YouTube videos or Netflix -- then a Chromebook is an amazing value. Unlike Windows machines, they're nearly impervious to viruses, they boot up almost instantaneously, and they never need to install software updates.

Certainly, Chromebooks aren't for everyone, but if you're one of the growing number of people who spend their time almost exclusively in a browser window, then Chromebooks offer the best value by far. There are about a dozen different models now, and they're not all that different from one another, but the Toshiba CB35 and Acer C720P stand out from the rest.