Laptop computers have been around for much longer than people imagine, though they’ve changed unimaginably from the first stumbling steps to the thin and powerful machines we have today. As far back as 1975 portables were an idea that computer manufacturers were keen to make the most of.

The first computer that could be referred to as a portable was made by IBM. The IBM 5100, however, was barely a laptop. The 5100 did have a screen and a keyboard, with number pad, built-in, but that’s where any comparisons with a modern laptop cease.

The screen was a 5in CRT that was capable of displaying just 16 lines of code and a maximum of 64 characters on each of those lines. A 1.9MHz processor powered the computer and it came in configurations with 16KB or 64KB of RAM. To top it off the unit weighed in at a beefy 24KG.

Of course, by any modern understanding of a portable computer the IBM is nothing more than a computer that you could move about and certainly not a laptop, but getting a computer into such a small form factor was, at the time and astonishing feat.

One of the first, if not the first computer that used the flip top form was from a company called Dulmison who made the evocatively named Dulmont Magnum. It had a keyboard at the front with a hinged screen that folded flat over it. The Dulmont wasn’t much of a success, but the seed was planted and larger competitors such as HP were quick to see the appeal of this design and take advantage.

With the general format set in motion the laptop form took a variety of forms around the same general theme until Apple released the PowerBook 100 line in the early 1990s. The design of the PowerBook included a few touches that would be mimicked by the rest of the industry and set the tone for what a laptop computer should be. Apple pushed the keyboard back to give the device palm rests and to make way for the central trackball and mouse buttons. Though these seem minor today the basic design of a laptop hasn’t changed much since.

Once the format of the modern laptop design had been set there were hundreds of machines from many manufacturers all with minor changes here and there. Larger screens, up to 17in in some cases, with better resolutions, Blu-ray drives, SSD hard disks and a host of other additions such as Bluetooth and Wi-Fi have all become standard on portable machines.

For a while it looked like the netbook might take over from the standard laptop form factor. These mini-laptops were much the same as standard sized machines, but weighed less and took up much less room when on the move. Importantly, netbooks were often powerful enough to take on the everyday tasks of most laptop users like web browsing and emails. It’s not that netbook type computers weren’t already around as the Psion Series of pocketable computers could, arguably, fall in to the netbook category. However, the first mass produced computer that could really be called a netbook was most likely the Eee PC from Asus.

The Eee PC 700 had a 7in screen and came with Linux instead of Microsoft Windows, but it had all the ingredients of a laptop, just much smaller. The keyboard and trackpad were all there and the Eee PC used a fast, if small, SSD as it’s main storage space. The low cost and small footprint initially appealed to many users, but over time the netbook star waned as ultrabooks and tablets started to replace the need for exceptional small and lightweight portable computers.

Which leads us to today and perhaps to the most evolved of all the laptop formats; the convertible.

For example, the XPS-12 from Dell combines a top of the range traditional laptop format and a tablet in one. The XPS 12 comes with either Intel Core i5 or i7 processors running at an astonishing 3.1GHZ and has a 12.5in HD touch screen, compare that to the IBM that kicked off the portable computing craze back in 1975 and it’s quite unimaginable how much things have changed.

The screen is hinged in the centre as well as the base so that you can easily transform it from a traditional laptop into a tablet with just the slightest touch. No matter what your needs the Dell pivots perfectly between business machine with a proper keyboard and trackpad to tablet that’s perfect for lazily browsing the web and watching movies, reading books, playing games and more.

The award-wining design of the XPS12 is just one facet of the device. Carbon fibre, Corning Gorilla Glass and precision cut aluminium are all used to bring incredibly strength and flexibility in a product that remains lightweight and useable everyday.

With all that power and flexibility in the hardware you need the software to match and with Windows 8 the Dell has a perfect companion. At home with mouse and keyboard input Windows 8 is now fully touch compatible too.

Assessing at the history of laptop and portable computer design it’s amazing to look back and see just how much things have changed. The first portable computer was merely that, a computer that could be moved. Through the decades however, we’ve seen refinement after refinement and multiple subtle changes that leads us to today where a laptop can be three things in one go.

Powerful desktop replacement and on the go mobile computer as well as a fully -featured tablet PC to boot. With devices such as the latest convertible laptops currently leading in the design stakes, it’s exciting to think what more might change in the years to come.

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