A laptop computer, also known as a notebook computer, is a small personal computer designed for portable use. A laptop integrates all of the typical components of a desktop computer, including a display screen, a keyboard, a pointing device (a touchpad, also known as a trackpad, or a pointing stick) and a battery into a single portable unit. The rechargeable battery is charged from an AC/DC adapter and has enough capacity to power the laptop for a few hours. The display may or may not have a touch screen.
 eBook Use
A laptop can typically support all or at least most of the eBook formats. However it is often too big or heavy to be used in a mobile environment. It is also inconvenient in that the keyboard is in the way and most screens cannot be rotated to facilitate portrait eBook viewing. In addition battery life on these units is only a few hours which would require frequent recharges to read a book. To overcome these problems there have been developed more mobile devices that are smaller, less power hungry, and cheaper than a laptop while attempting to provide some or all of a laptop's functionality. These include:
- ULCPC - Ultra Low Cost PC, also known as netbook, sub-notebook.
- Tablet PC - touch screen
- 2-in-1 - A Tablet with a removable keyboard often similar in size to a netbook.
- UMPC - Ultra Mobile PC
- MID - Mobile Internet Device
- Ultrabook - super thin with good battery life.
A laptop can often weigh 8 lbs or more and can be as big as a brief case. Even with all these negatives many people will use them to read eBooks and there are many programs available that can be used with Windows, MacOS X, and Linux computers. Some use them in conjunction with a more portable unit particularly if they don't own a desktop PC and many eBook formats are available for both a portable device and a laptop permitting sharing of eBooks. In a few cases you can even sync between the portable device and the main computer so that you can start a book on one and pick up where you left off on the second machine.
The Dynabook is widely considered to be the inspiration for the modern portable computer. Conceived by Alan Kay in 1968 at Xerox PARC, the device was envisioned as "a personal computer for children of all ages."
The 12-pound Grid Compass 1100 -- the first computer to use a fold-up, clamshell case -- brings us closer to a modern-looking laptop design. Originally designed for NASA and available to consumers in 1982, the Compass 1100 carried 340KB of memory and cost about $8,000 including software and a mandatory maintenance agreement. Despite its place in laptop history, the Grid didn't survive long in the marketplace because it wasn't IBM compatible. The Dulmont Magnum built in Australia was available in the same time frame.
The Radio Shack Model 100 was introduced in 1983, it sold over 6 million units. It was one of the first-ever truly notebook computers. It had a built-in modem for connecting to bulletin boards and CompuServe, as well as corporate systems. Even with the limited memory (24K), you could still type about 12 pages of text. You could write programs to store other types of data and then use the modem to transmit it to other systems. The LCD screen was 8 lines of 40 characters. Graphics mode was 240 x 64 pixels.
The Kaypro 2000 was introduced in 1985. It was IBM compatible and had a brushed aluminum clamshell case which made it look very much like the modern laptop design. It featured a 25 line by 80 character LCD display, a detachable keyboard, and a 3.5" floppy drive. IBM made their first LCD laptop, the IBM PC Convertible, in 1986. It had a CGA screen and weighed 13 lbs.
In October 1988, the Compaq SLT/286 debuted. The first computer to use VGA (640 x 480 resolution) graphics, it revolutionized portable displays. The SLT/286 weighed 14 pounds and had a 20MB hard drive, a 12MHz processor, and a keyboard that you could detach from the main body of the machine.
The next big jump in laptops following the Compaq SLT/286 came in 1991, when the Apple PowerBook 100 arrived. Made for Apple by Sony, the PowerBook 100 featured a trackball to serve as the mouse, and a palm rest to make working on the computer more comfortable; soon palm rests became a standard feature on laptops from many other vendors.
In late 1992, IBM took the compact design of the PowerBook's pointing device a step further in its new ThinkPad series -- most notably the $4,350 ThinkPad 700C, which ran Windows 3.1 and had a 120MB hard drive, a 25MHz 486SLC CPU, and a large and lovely 10.4-inch color TFT active-matrix panel. Touchpads, also known as a trackpads were originally used on the Apollo desktop computer but later adapted to laptop use in the '90's.
After that laptops haven't changed much but keep getting more powerful.