There are now three different models of MacBook in Apple's line-up: MacBook Air, MacBook Pro and MacBook Pro with Retina display. Further still, each of those MacBooks is available in different sizes and configurations, with various build-to-order options. It's not surprising, then, that many people have difficulty deciding between them.

Here, we're helping you make that decision by examining the options and providing expert advice about which MacBook is best for you.

First, let's take a look at what's on offer.

There are four configurations of MacBook Air available. Two have an 11in display and two have a 13in display. Each size has a 128GB and 256GB offering. The MacBook Air is the most portable MacBook available, particularly the 11in model, so it's ideal for anyone who travels a lot.

When it comes to the MacBook Pro, there are a total of five Retina display models, three of which have 13in screens while the remaining two have 15in displays. They offer more power than the MacBook Air, and the display is significantly better screen resolution. Internally, each of the MacBook Pro with Retina display models differ, but we'll come to that later.

The final MacBook available (which makes 10 in total) is the lonely MacBook Pro (without Retina display). It's only available as a 13in 2.5GHz model, but it's the last remaining MacBook with an optical-drive.

Of course, there are also build-to-order options, but here we're focusing on the 10 configurations Apple advertises on its website.

To figure out which MacBook will best suit your needs, you'll need to think about what's most important. Are you looking for a MacBook to take with you on business trips? Perhaps you're after a gaming machine, or you're a student who needs a MacBook for uni. Here, we take you through the options.

You could also watch this video where we discuss whether you should buy the 13-inch MacBook Pro with Retina display, or the slightly cheaper 13-inch MacBook Air

Read more here

Which MacBook should I buy for portability?

The 11in MacBook Air is the lightest and thinnest MacBook available, with a height of 1.7cm and a weight of 1.08 kg. Therefore, it's ideal for carrying with you on business trips or in your bag on the way to work.

The actual screen size of the smallest MacBook Air is 11.6 inches, which is just 1.9 inches bigger (diagonally) than the iPad Air.

If you're worried that you might find this a little bit too small, but you're settled on the idea of buying a MacBook Air, you can watch our which MacBook Air is best video below.

You can also find out more in our which MacBook Air is best article.

You'll get iWork for free when you buy a new MacBook Air, which means you'll be able to use Apple's Pages, Numbers and Keynote applications (the rivals to Microsoft's Word, Excel and PowerPoint). However, you'll get the same if you opt for one of Apple's other Macs, too.

Also, the battery life of the 13in MacBook Air is the highest of any MacBook available. Apple calls it an "all-day battery" but what that means is up to 12 hours, and a whopping 30 days standby time.

If you decide that a 13in MacBook is definitely the size for you, then there's actually little difference in weight and thickness between the Air and the Pro now that Apple has made the MacBook Pro even thinner and lighter than before.

The 13in MacBook Air is 1.7cm thick and weighs 1.35kg, while the 13in Retina MacBook Pro is just a little heavier, at 1.57 kg, and a tiny bit thicker at 1.8cm.

To help you decide between these two models, you can read our which 13in Apple laptop article.

Which MacBook should I buy for running applications like Adobe Photoshop?

If you want to use your MacBook for more powerful tasks like running creative applications, then the MacBook Air might not be the best option.

If you're a graphic designer, video editor or photographer, then the likelihood is you'll benefit from a bigger display. There's no longer a 17in MacBook Pro option, but there are two 15in MacBook Pro with Retina display models available.

The first has a 2.0GHz quad-core Intel Core i7 processor with Turbo Boost up to 3.2Ghz. It has 8GB 1600MHz memory and 256GB flash storage.

The second has a 2.3GHz quad-core Intel Core i7 processor with Turbo Boost up to 3.5GHz and 16GB or 1600MHz memory. It has 512GB of flash storage.

Thanks to the Crystalwell processors, both of the 15in MacBook Pro models have Intel Iris Pro Graphics. To find out more about Crystalwell and what it means, visit our What is Crystalwell article. The second of the two models has NVIDIA GeForce GT 750M with 2GB of GDDR5 video memory and automatic GPU switching, too.

However, these MacBook Pro models don't come cheap. The cheapest 15in model available is £1,699, while the high-end model is £2,199.

If you want to boost the storage or add a better processor, it'll add to the price, too. However, if you're working on large files, the 1TB flash storage option could be very useful, but it'll cost you an extra £400.

Which MacBook should I buy for gaming?

The Mac is growing in popularity as a gaming machine, especially since the launch of the Mac App Store. Plus, the ability to install Windows via Boot Camp on a Mac means Mac gamers can run Windows games too.

If you want to buy a MacBook for gaming, then we'd recommend the (unfortunately most expensive) high-end MacBook Pro with Retina display. It's got NVIDIA GeForce GT 750M with 2GB graphics, which should provide the best performance out of all of the MacBooks available.

However, even the 13in MacBook Pro models have significantly improved graphics performance, with Apple claiming that they're 90 per cent faster thanks to Intel HD Graphics 4000.

Which MacBook should I buy if I'm on a budget?

If money is the deciding factor when it comes to buying a MacBook, then the cheapest model available is the 128GB 11in MacBook Air, which costs £849. At £100 more, you can get the 13in MacBook Air, and add another £50 to that and you can buy the non-Retina MacBook Pro for £999.

However, it's also worth taking a look on Apple's refurbished store, which often has MacBooks available to buy at reduced prices. Apple puts the products in the refurbished store through vigorous testing, so you'll hardly know the difference between a refurbished Mac and a brand new one.

The cheapest MacBook we can see on the Apple refurbished store at time of writing is a June 2014 11in MacBook Air with 128GB flash storage, which has a saving of £130, making it £719.

See: Should I buy a secondhand Mac?

[Wondering whether to buy a MacBook or a Mac desktop? Find out if you should buy a Mac laptop or Mac desktop here.]

Which MacBook should I buy for university?

We'd suggest that students will have similar needs to business users. They'll want to be able to carry their MacBook to and from lectures, and probably won't need them to be hugely powerful (unless they're on a graphic design or video editing course…).

In that case, we'd suggest the MacBook Air again. Take a look back at the advice we gave at the beginning of this article when discussing portability for more information.

However, it's worth noting that the Retina-less MacBook Pro still has an optical drive, and, surprisingly, some universities still require work to be submitted on a CD or DVD. However, Apple does sell an external optical drive for £65.

Which MacBook should I buy for storage?

The maximum storage available for the MacBook Air is 512GB, but with the MacBook Pro, you can configure your model to give it a 1TB flash drive for an additional £400.

If you're still undecided about which MacBook to buy, below are some links that may come in useful.

10 reasons why Macs are better than PCs

Apple MacBook Pro with Retina display review

MacBook Air vs Windows laptops: which is best?

See also:

Which cables, adapters and accessories do you need for the Apple MacBook Air and Pro laptops