The first "portable" computers were often called "luggables." The size of a portable sewing machine, they tipped the scales at 30 pounds. Equipped with a small CRT display, they were actually a traditional PC in a slightly smaller case. The real change in portable computers came with the advent of the flat-panel display, allowing the portable to take on the now-familiar slim design. "Laptop" is the term used for the heavier version, usually offering most of the features of a full-fledged PC, but with a folding flat-panel display and integrated keyboard. Notebooks are slender devices that often lack the full range of storage as part of the normal configuration. PDAs, a special group of products offering a subset of features including e-mail, schedule-tracking, contact records, and allowing limited note-taking and Web-browsing, are beyond the scope of this tutorial.
With advancements in battery technology and the advent of functional large-screen LCDs (liquid crystal displays), the first truly portable computers, referred to as laptops, were produced in the late 1980s. These units featured integrated AT-compatible computer boards, including I/O and video controller functions. Laptops, as mentioned, usually feature a folding LCD display and a built-in keyboard and pointing device. They also use an external power supply and a removable, rechargeable battery. Today's laptops have fairly large (2 GB or more) hard drives, a CD-ROM drive, and floppy disk drive (often the latter two are interchangeable plug-ins).
When laptops originally appeared on the market, they were the smallest portable computers made. Today, they are high-end machines that offer features and performance comparable to a desktop system.
Advancements in integrated circuit (IC) technology allowed the size of computer components to be reduced even further, and in the early- to mid- 1980s the notebook computer was born. Notebooks are roughly 8.75 inches deep, by 11 inches wide, by 2.25 inches thick, and designers are working to decrease the size and power consumption of these units even further. The reduction in size comes at a cost, however, and notebooks typically have smaller and less-capable displays and keyboards than laptops. A wide variety of specialty items have appeared on the market intending to overcome some of the notebook's shortcomings. Docking ports are one such item.
Docking ports (also known as docking stations) are specialized cases into which an entire notebook can be inserted. This allows the notebook to be connected to desktop I/O devices such as full-sized keyboards, CRT monitors, and network connections. At the very minimum, a docking station provides an AC power source for the notebook. Docking stations are highly proprietary items that are designed for use with specific computer models. They are handy for the user who wants to maintain only one computer system and avoid the necessity of transferring information between two systems. With a docking port and a well-equipped notebook computer, it is possible to have the best of both worlds.
It is not necessary to have a docking port to use a portable computer with a full-sized keyboard, pointing device, and monitor. Most portables have standard connectors for these peripherals. Be aware that you might have to connect the devices before booting up the computer, though.
Subnotebook (Palmtop) Computers
Even smaller than the notebook computers are subnotebook computers, also known as palmtops. These tiny systems are 7 inches wide, by 4 inches deep, by 1 inch high. Due to their size, they are rather limited in function. Keyboards, for example, are too small to permit touch typing. With notebooks decreasing in cost and weight, palmtops have been losing market share and popularity.