Название: Laptops For Dummies
Автор: Gookin Dan
Издательство: Автор
Жанр: Зарубежная образовательная литература
isbn: 9781119041818
isbn:
Figure 1-5: The Compaq SLT.
The Compaq SLT was the first portable computer to resemble a modern laptop: A hinged lid swings up and back from the base, which contains the keyboard. This design is known as the clamshell.
Feature-wise, the SLT had what most PC desktop users wanted in a portable system: a full-size keyboard, full-size screen, floppy drive, and 286 processor, which meant that the computer could run the then-popular DOS operating system. The computer lacked a hard drive.
Weight? Alas, the SLT was a bowling ball, at 14 pounds!
What the Compaq SLT did was prove to the world that portability was possible. A laptop computer was designed to feature everything a desktop computer could, and run on batteries for an hour or so. Yeah, believe it or not, people were delighted.
Calculating laptop weight: The missing pieces
When computer companies specify the weights of their laptops, I’m certain that they do it under ideal conditions, possibly on the moon or at another location where gravity is weak. The advertised weight is, as they say, "for comparison purposes only."
Commonly left out of the laptop’s weight specs is the power brick, the AC adapter that connects the laptop to a wall socket. When the laptop isn’t running on batteries, you need the power brick to supply the thing with juice, so the power brick is a required accessory – something you have to tote with you if you plan to take the laptop on an extended trip.
Back when laptops were novel, the advertisements never disclosed how much the power brick weighed – sometimes half as much as the laptop itself! Either that or the power brick was even bulkier than the laptop, as shown in the figure, in the obnoxiously big Dell 320LT power brick (and its cumbersome 30-minute batteries). Lugging around those items isn’t convenient. Things are better today.
Just because the marketing department labeled the computer a laptop didn’t mean that it was sleek and lightweight. For a while there, it seemed like anyone could get away with calling a portable PC a laptop, despite the computer’s weight of up to 20 pounds – which is enough to crush any lap, not to mention kneecaps.
In the fall of 1989, NEC showed that it could think outside the laptop box when it introduced the UltraLite laptop, shown in Figure 1-6.
Figure 1-6: The NEC UltraLite.
The UltraLite featured a full-size screen and keyboard but no disk drives or other moving parts! It used battery-backed-up memory to serve as a silicon disk, similar to today’s solid-state drives (SSDs). The silicon disk stored 1 or 2MB of data – which was plenty back in those days.
As was required of all laptops, the UltraLite featured a modem, and it could talk with a desktop computer by using a special cable. Included with the UltraLite was software that would let it easily exchange files and programs with a desktop PC.
The weight? Yes, the UltraLite lived up to its name and weighed in at just under 5 pounds – a feather compared to the obese laptops of the day. And the battery lasted a whopping two hours, thanks mostly to the UltraLite’s lack of moving parts.
Modern Laptops
As technology careened headlong into the 21st century, it became apparent that computer users were desperate for three things from their laptops – in addition to the basic PC compatibility, portability, and communications features that had long ago been deemed must-have items:
✔ Light weight
✔ Long battery life
✔ Full hardware compatibility with desktop systems
Over time, all these qualities were achieved – at a price. Today, the holy grail of a lightweight, PC-compatible laptop that boasts a long battery life isn’t elusive; it’s just expensive!
The modern PC laptop is dubbed a notebook. It can sport a full-size keyboard and numeric keypad but often has a compact keyboard. The notebook weighs in anywhere from 2 to 6 pounds, and the battery lasts somewhere between 4 to 6 hours.
The rest of the typical notebook is similar to a desktop PC: LCD screen, wired and wireless networking. Some systems even sport an optical drive (CD and DVD). Putting all these features into a laptop computer gives you today’s notebook.
Human laps aren’t getting any smaller. Human eyes can comfortably read text that’s only so big. Most important, human fingers have trouble with keyboards that are too tiny. Despite these limitations, a popular notebook category is the subnotebook, which is the smallest, lightest, and most portable type of laptop.
Several kinds of subnotebooks are available, such as the Ultrabook, netbook, and the Ultra Mobile PC (UMPC). Each of these offers compromises on the notebook design, primarily to accommodate for the smaller size and weight. Figure 1-7 illustrates a typical netbook computer.
Figure 1-7: The eensy-weensy netbook PC.
Computer manufacturers have long attempted to create the electronic equivalent of a pencil and pad of paper – a very expensive pencil and pad of paper. Basically, what they’re after is a portable computer with a monitor but no keyboard. Data is input by using a digital stylus to write directly on the screen.
Over the years, this digital triptych has had various names attached to it: the PenGo computer, the Apple Newton, Pen Windows, and eventually the tablet PC.
The tablet PC can be one of two things. First, it can be a traditional laptop or notebook, but one that features a touchscreen interface. The screen can even bend and twist to cover the keyboard. This type of system might also be called a convertible laptop.
An even lighter and thinner version of the tablet PC exists, such as the Microsoft Surface shown in Figure 1-8. These computers are essentially laptops without a keyboard, although the keyboard is often included as a type of cover.
Figure 1-8: A tablet PC.
Tablet PCs can offer pen input by using a digital pen or stylus. This device effectively brings the laptop quest full circle to a pad of paper and pencil, although fully entrenched in the digital realm.
✔ Don’t confuse the tablet PC with mobile devices, such as the iPad or Samsung Galaxy Tab. A tablet PC differs from these gizmos in that it offers features associated СКАЧАТЬ