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An ultraportable IBM X31 with 12" screen on an IBM T43 Thin & Light laptop with a 14" screen
QWERTY keyboard on 2007 Sony VAIO laptop
A laptop computer, or simply laptop (also notebook computer, notebook and notepad) is a small mobile computer, which usually weighs 2-18 pounds (around 1 to 8 kilograms), depending on size, materials, and other factors.
Laptops usually run on a single main battery or from an external AC/DC adapter that charges the battery while also supplying power to the computer itself. Many computers also have a 3 volt cell to run the clock and other processes in the event of a power failure.
Laptops contain components that are similar to their desktop counterparts and perform the same functions, but are miniaturized and optimized for mobile use and efficient power consumption, although typically less powerful for the same price. Laptops usually have liquid crystal displays and most of them use different memory modules for their random access memory (RAM), for instance, SO-DIMM in lieu of the larger DIMMs. In addition to a built-in keyboard, they may utilize a touchpad (also known as a trackpad) or a pointing stick for input, though an external keyboard or mouse can usually be attached.
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Laptops can be understood as a particular point on the continuum of more or less portable computing devices: the point at which the device is large enough to use substantially the same software as a desktop machine, but small enough to support mobile computing. Other points on the continuum include:
Boundaries that separate these categories are blurry at times. For example, the OQO UPC is a PDA-sized tablet PC; the Apple eMate had the clamshell form factor of a laptop, but ran PDA software. The HP Omnibook line of laptops included some devices small enough to be called handheld computers. The hardware of the Nokia 770 internet tablet is essentially the same as that of a PDA such as the Zaurus 6000; the only reason it\'s not called a PDA is that it doesn\'t have PIM software. On the other hand, both the 770 and the Zaurus can run some desktop Linux software, usually with modifications.
An opened Osborne 1 computer, ready for use. The keyboard sits on the inside of the lid.
Before laptop/notebook computers were technically feasible, similar ideas had been proposed, most notably Alan Kay\'s Dynabook concept, developed at Xerox PARC in the early 1970s.
The first commercially available portable computer was the Osborne 1 in 1981, which used the CP/M operating system. Although it was large and heavy compared to today\'s laptops, with a tiny CRT monitor, it had a near-revolutionary impact on business, as professionals were able to take their computer and data with them for the first time. This and other "luggables" were inspired by what was probably the first portable computer, the Xerox NoteTaker, again developed at Xerox PARC, in 1976; however, only ten prototypes were built. The Osborne was about the size of a portable sewing machine, and importantly could be carried on a commercial aircraft. However, it was not possible to run the Osborne on batteries: it had to be plugged into mains.
In 1982 Kaypro introduced the Kaypro II, a CP/M-based competitor to the Osborne 1. The Kaypro II featured a display nearly twice as big as the Osborne\'s and double-sided floppy drives with twice the storage capacity.
Although it wasn\'t released until 1985, well after the decline of CP/M as a major operating system, the Bondwell 2 is one of the only CP/M laptops. It used a Z-80 running at 4 MHz, had 64 K RAM and, unusually for a CP/M machine, a 3.5" floppy disk drive built in. It had a 80x25 character-based LCD mounted on a hinge similar to modern laptops, one of the first computers to use this form factor.
A more enduring success was the Compaq Portable, the first product from Compaq, introduced in 1983, by which time the IBM Personal Computer had become the standard platform. Although scarcely more portable than the Osborne machines, and also requiring AC power to run, it ran MS-DOS and was the first true IBM clone (IBM\'s own later Portable Computer, which arrived in 1984, was notably less IBM PC-compatible than the Compaq[citation needed]).
Another significant machine announced in 1981, although first sold widely in 1983, was the Epson HX-20. A simple handheld computer, it featured a full-transit 68-key keyboard, rechargeable nickel-cadmium batteries, a small (120 x 32-pixel) dot-matrix LCD display with 4 lines of text, 20 characters per line text mode, a 24 column dot matrix printer, a Microsoft BASIC interpreter, and 16 KB of RAM (expandable to 32 KB).
However, arguably the first true laptop was the GRiD Compass 1101, designed by Bill Moggridge in 1979-1980, and released in 1982. Enclosed in a magnesium case, it introduced the now familiar clamshell design, in which the flat display folded shut against the keyboard. The computer could be run from batteries, and was equipped with a 320×200-pixel plasma display and 384 kibibyte bubble memory. It was not IBM-compatible, and its high price (US$8,000–10,000) limited it to specialized applications. However, it was used heavily by the U.S. military, and by NASA on the Space Shuttle during the 1980s. The GRiD\'s manufacturer subsequently earned significant returns on its patent rights as its innovations became commonplace. GRiD Systems Corp. was later bought by the Tandy (now RadioShack) Corporation.
The AmpereBob Armstrong, http://cosy.com/language/cosyhard/cosyhard.htm a sleek clamshell design by Ryu Oosake also debuted in 1983. It offered a MC68008 microprocessor dedicated to running an APL interpreter residing in Read Only Memory.
Two other noteworthy early laptops were the Sharp PC-5000 and the Gavilan SC, announced in 1983 but first sold in 1984. The Gavilan was notably the first computer to be marketed as a "laptop". It was also equipped with a pioneering touchpad-like pointing device, installed on a panel above the keyboard. Like the GRiD Compass, the Gavilan and the Sharp were housed in clamshell cases, but they were partly IBM-compatible, although primarily running their own system software. Both had LCD displays, and could connect to optional external printers. The Dulmont Magnum, launched internationally in 1984, was an Australian portable similar in layout to the Gavilan, which used the Intel 80186 processor.http://www.old-computers.com/museum/doc.asp?c=764
The year 1983 also saw the launch of what was probably the biggest-selling early laptop, the Kyocera Kyotronic 85. Owing much to the design of the previous Epson HX-20, and although at first a slow seller in Japan, it was quickly licensed by Tandy Corporation, Olivetti, and NEC, who recognised its potential and marketed it respectively as the TRS-80 Model 100 line (or Tandy 100), Olivetti M-10, and NEC PC-8201.See TRS-80 Model 100 / 102 at old-computers.com The machines ran on standard AA batteries. The Tandy\'s built-in programs, including a BASIC interpreter, a text editor, and a terminal program, were supplied by Microsoft, and are thought to have been written in part by Bill Gates himself. The computer was not a clamshell, but provided a tiltable 8×40-character LCD screen above a full-travel keyboard. With its internal modem, it was a highly portable communications terminal. Due to its portability, good battery life (and ease of replacement), reliability (it had no moving parts), and low price (as little as US$300), the model was highly regarded, becoming a favorite among journalists. It weighed less than 2 kg with dimensions of 30×21.5×4.5 centimeters (12×8½×1¾ in). Initial specifications included 8 kilobytes of RAM (expandable to 24 KB) and a 3 MHz processor. The machine was in fact about the size of a paper notebook, but the term had yet to come into use and it was generally described as a "portable" computer.
Possibly the first commercial IBM-compatible laptop was the Kaypro 2000, introduced in 1985. With its brushed aluminum clamshell case, it was remarkably similar in design to modern laptops. It featured a 25 line by 80 character LCD display, a detachable keyboard, and a pop-up 90 mm (3.5 inch) floppy drive.
Also among the first commercial IBM-compatible laptops were the IBM PC Convertible, introduced in 1986, and two Toshiba models, the T1000 and T1200, introduced in 1987. Although limited floppy-based DOS machines, with the operating system stored in read-only memory, the Toshiba models were small and light enough to be carried in a backpack, and could be run off lead-acid batteries. These also introduced the now-standard "resume" feature to DOS-based machines: the computer could be paused between sessions, without having to be restarted each time.
The first laptops successful on a large scale came in large part due to a Request For Proposal (RFP) by the U.S. Air Force in 1987. This contract would eventually lead to the purchase of over 200,000 laptops. Competition to supply this contract was fiercely contested and the major PC companies of the time; IBM, Toshiba, Compaq, NEC, and Zenith Data Systems (ZDS), rushed to develop laptops in an attempt to win this deal. ZDS, which had earlier won a landmark deal with the IRS for its Z-171, was awarded this contract for its SupersPort series. The SupersPort series was originally launched with an Intel 8086 processor, dual floppy disk drives, a backlit, blue and white STN LCD screen, and a NiCD battery pack. Later models featured an Intel 80286 processor and a 20 MB hard disk drive. On the strength of this deal, ZDS became the world\'s largest laptop supplier in 1987 and 1988. ZDS partnered with Tottori Sanyo in the design and manufacturing of these laptops. This relationship is notable because it was the first deal between a major brand and an Asian original equipment manufacturer.
Another notable computer was the Cambridge Z88, designed by Clive Sinclair, introduced in 1988. About the size of an A4 sheet of paper as well, it ran on standard batteries, and contained basic spreadsheet, word processing, and communications programs. It anticipated the future miniaturization of the portable computer, and as a ROM-based machine with a small display, can—like the TRS-80 Model 100—also be seen as a forerunner of the personal digital assistant.
By the end of the 1980s, laptop computers were becoming popular among business people. The NEC UltraLite, released in mid-1989, was perhaps the first notebook computer, weighing just over 2 kg; in lieu of a floppy or hard drive, it contained a 2 mebibyte RAM drive, but this reduced its utility as well as its size. The first notebook computers to include hard drives were those of the Compaq LTE series, introduced toward the end of that year. Truly the size of a notebook, they also featured grayscale backlit displays with CGA resolution.
The Macintosh Portable, Apple\'s first attempt at a battery-powered computer
The first Apple Computer machine designed to be used on the go was the 1989 Macintosh Portable (although an LCD screen had been an option for the transportable Apple IIc in 1984). Unlike the Compaq LTE Laptop Released earlier in the year the Macintosh Portable was actually a "luggable" not a laptop, but the Mac Portable was praised for its clear active matrix display and long battery life, but was a poor seller due to its bulk. In the absence of a true Apple laptop, several compatible machines such as the Outbound Laptop were available for Mac users; however, for copyright reasons, the user had to supply a set of Mac ROMs, which usually meant having to buy a new or used Macintosh as well.
The Apple PowerBook series, introduced in October 1991, pioneered changes that are now de facto standards on laptops, such as room for a palm rest, and the inclusion of a pointing device (a trackball). The following year, IBM released its ThinkPad 700C, featuring a similar design (though with a distinctive red TrackPoint pointing device).
Later PowerBooks introduced the first 256-color displays (PowerBook 165c, 1993), and first true touchpad, first 16-bit sound recording, and first built-in Ethernet network adapter (PowerBook 500, 1994).
In 1994, IBM released RS/6000 N40 PowerPC laptop running AIX (Operating system based on UNIX), manufactured by Tadpole. Tadpole also manufactured laptops based on SPARC and DEC Alpha CPUs.
The summer of 1995 was a significant turning point in the history of notebook computing. In August of that year Microsoft introduced Windows 95. It was the first time that Microsoft had placed much of the power management control in the operating system. Prior to this point each brand used custom BIOS, drivers and in some cases, ASICs, to optimize the battery life of its machines. This move by Microsoft was controversial in the eyes of notebook designers because it greatly reduced their ability to innovate; however, it did serve its role in simplifying and stabilizing certain aspects of notebook design. Windows 95 also ushered in the importance of the CD-ROM drive in mobile computing, and initiated the shift to the Intel Pentium processor as the base platform for notebooks. The Gateway Solo was the first notebook introduced with a Pentium processor and a CD-ROM. Also featuring a removable hard disk drive and floppy drive, the Solo was the first three-spindle (optical, floppy, and hard disk drive) notebook computer, and was extremely successful within the consumer segment of the market. In roughly the same time period the Dell Latitude, Toshiba Satellite, and IBM ThinkPad were reaching great success with Pentium-based two-spindle (hard disk and floppy disk drive) systems directed toward the corporate market.
As technology improved during the 1990s, the usefulness and popularity of laptops increased. Correspondingly prices went down. Several developments specific to laptops were quickly implemented, improving usability and performance. Among them were:
Hard disk from a Dell Latitude
Most modern laptops feature 12 inch (30 cm) or larger active matrix displays with resolutions of 1024×768 pixels and above, and have a PC Card (formerly PCMCIA) or ExpressCard expansion bay for expansion cards. Internal hard disks are physically smaller—2.5 inch (60 mm)—compared to the standard desktop 3.5 inch (90 mm) drive, and usually have lower performance and power consumption. Video and sound chips are usually integrated. This tends to limit the use of laptops for gaming and entertainment, two fields which have constantly escalating hardware demands.[1] However, higher end laptops can come with dedicated graphics processors, such as the Dell Inspiron E1505 and E1705, which can be bought with an ATI Mobility Radeon X1300 or similar. These mobile graphics processors tend to have less performance than their desktop counterparts, but this is because they have been optimized for lower power usage.
There is a wide range of laptop specific processors available from Intel (Pentium M, Celeron, Intel Core and Intel Core 2) and from AMD (Athlon, Turion 64, and Sempron) and also from VIA (C3 and C7-M). Motorola and IBM developed and manufactured the chips for the former PowerPC-based Apple laptops (iBook and PowerBook). Generally, laptop processors are less powerful than their desktop counterparts, due to the need to save energy and reduce heat dissipation. However, the PowerPC G3 and G4 processor generations were able to offer almost the same performance as their desktop versions, limited mostly by other factors, such as the system bus bandwidth; recently, though, with the introduction of the G5s, they have been far outstripped. At one point, the Pismo G3, at up to 500 MHz, was faster than the fastest desktop G3 (then the B&W G3), which ran at 450 MHz.
Some parts for a modern laptop have no corresponding part in a desktop computer. For example, current models use lithium ion and more recently lithium polymer batteries, which have largely replaced the older nickel metal-hydride technology. Typical battery life for most laptops is two to five hours with light-duty use, but may drop to as little as one hour with intensive use. Batteries gradually deteriorate over time and eventually need to be replaced in one to five years, depending on the charging and discharging pattern.
Docking stations became another common laptop accessories in the early 1990s. They typically were quite large and offered 3.5" and 5.25" storage bays, one to three expansion slots (typically AT style), and a host of connectors. The mating between the laptop and docking station was typically through a large, high-speed, proprietary connector. The most common use was in a corporate computing environment where the company had standardized on a common network card and this same card was placed into the docking station. These stations were very large and quite expensive. As the need to additional storage and expansion slots became less critical because of the high integration inside the laptop itself, the emergence of the Port Replicator as a major accessory commenced. The Port Replicator was often a passive device that simply mated to the connectors on the back of the notebook and allowed the user to quickly connect their laptop so VGA, PS/2, RS-232, etc. devices were instantly attached. As higher speed ports like USB and Firewire became commonplace, the Port Replication was accomplished by a small cable connected to one of the USB 2.0 or FireWire ports on the notebooks. Wireless Port Replicators followed.
Virtually all laptops can be powered from an external AC converter. This device typically adds half a kilogram (1 lb) to the overall "transport weight" of the equipment.
A pointing stick or touchpad is used to control the position of the cursor on the screen. The pointing stick is usually a rubber dot that is located between the G, H and B keys on the laptop keyboard. To navigate the cursor, pressure is applied in the direction intended to move. The touchpad is touch-sensitive and the cursor can be navigated by moving the finger on the pad.
Intel, Asus, Compal, Quanta and other laptop manufacturers have created Common Building Block standard for laptop parts.
Current compatibility problems in the laptop trade are reflective of the early era of personal computer hardware, when there were many different manufacturers, each and every one of them having their own connectivity and mounting systems and incompatibility was the norm. While there are accepted world standards of form factors for all the peripherals and add-in PC cards used in the desktop computers, there are still no firm worldwide standards relating to today\'s laptops\' internal form factors, such as supply of electric voltage, motherboard layouts, internal adapters used in connecting the optical drive, LCD cable, keyboard and floppy drive to the main board. Most affected by this are users uneducated in the relevant fields, especially if they attempt to connect their laptops with incompatible hardware or power adapters.
Some parts, such as hard drives and memory are commodity items and are interchangeable. However, other parts such as motherboards, keyboards, and batteries are proprietary in design and are only interchangeable within a manufacters brand and/or model line.
A significant point to note is that the vast majority of laptops on the market are manufactured by a small handful of ODMs.Notebook OEM/ODM relationships. Retrieved on 2007-06-28. The ODM matters more than the OEM. Major relationships include:
Due to their portablility and tight integration, laptops are more subject to wear and physical damage than desktops. Components such as batteries, screen hinges, power jacks, and power cords are commonly subject to deterioration due to ordinary use. A liquid spill onto the keyboard, which is rather minor mishap with a desktop system can damage costly components such as the motherboard or LCD panel. Dropping a laptop can damage the LCD screen if not break apart its body. The repair costs of a failed motherboard or LCD panel may exceed the purchase value of the laptop.
Some manufacturers have mitigated some of these problems by selling "ruggedized" laptops. These often have a special drain in the keyboard that safely routes all of the water out through a hole in the bottom of the case. Additionally, the bodies of these laptops are typically made of magnesium alloy instead of plastic, and hard drives are often braced to greatly increase their chances of surviving a waist-high fall.
The main advantage of laptops over their larger desktop counterparts is the inherent portability. Another advantage is the laptop\'s ability to operate on battery power in the case of a power outage.
Laptops\' upgradeability is severely limited, both for technical and economic reasons. As of 2006, there is no industry-wide standard form factor for laptops. Each major laptop vendor pursues its own proprietary design and construction, with the result that laptops are difficult to upgrade and exhibit high repair costs. With few exceptions, laptop components can rarely be swapped between laptops of competing manufacturers, or even between laptops from the different product-lines of the same manufacturer. Standard feature peripherals (such as audio, video, USB, 1394, WiFi, Bluetooth) are generally integrated on the main PCB (motherboard), and thus upgrades often require using external ports, card slots, or wireless peripherals. Other components, such as RAM modules, hard drives, and batteries are typically user-upgradeable.
Many laptops have removable CPUs, although support for other CPUs is restricted to the specific models supported by the laptop motherboard. The socketed CPUs are perhaps for the manufacturer\'s convenience, rather than the end-user, as few manufacturers try new CPUs in last year\'s laptop model with an eye toward selling upgrades rather than new laptops. In many other laptops, the CPU is soldered and non-replaceable. Thus, there is no practical way to update it on models which already feature the latest processor for their motherboard.
Many laptops also include an internal MiniPCI slot, often occupied by a WiFi or Bluetooth card, but as with the CPU, the internal slot is often restricted in the range of cards that can be installed. The widespread adoption of USB mitigates I/O connectivity to a great degree, although the user must carry the USB peripheral as a separate item.
NVidia and ATI have proposed a standardized interface for laptop GPU upgrades (such as an MXM), but again, choices are limited compared to the desktop PCIe/AGP after-market.
In January 2007, Asus announced XG Station external video card for laptops. XG Station is connected to the laptops using USB-2 and Express card interface.
In February 2007, a new standard for external PCI Express cables and connectors was announced. Future laptops can be expanded using external PCI Express backplane and chassis.
A modern mid-range HP Laptop.
For a given price range (and manufacturing base), laptop computational power has traditionally trailed that of desktops. This is partly due to most laptops sharing RAM between the program memory and the graphics adapter. By virtue of their usage goals, laptops prioritize energy efficiency and compactness over absolute performance. Desktop computers and their modular components are built to fit much bigger standard enclosures, along with the expectation of AC line power. As such, energy efficiency and portability for desktops are secondary design goals compared to absolute performance.
For typical home (personal use) applications, where the computer spends the majority of its time sitting idle for the next user input, laptops of the thin-client type or larger are generally fast enough to achieve the required performance. 3D gaming, multimedia (video) encoding and playback, and analysis-packages (database, math, engineering, financial, etc.) are areas where desktops still offer the casual user a compelling advantage.
With the advent of dual-core processors and perpendicular recording, laptops are beginning to close the performance gap with desktops. Intel\'s Core 2 line of processors is efficient enough to be used in portable computers, and many manufacturers such as Apple, Lenovo and Dell are building Core 2 based laptops. Also, many high end laptop computers feature mobility versions of graphics cards, eliminating the performance losses associated with integrated graphics.
A study by State University of New York researchers says heat generated from laptops can significantly elevate the temperature of the scrotum, potentially putting sperm count at risk. The small study, which included little more than two dozen men ages 13 to 35, found that the sitting position required to balance a laptop can raise scrotum temperature by as much as 2.1 °C (3.8 °F). Heat from the laptop itself can raise the temperature by another 0.7 °C (1.4 °F), bringing the potential total increase to 2.8 °C (5.2 °F). However, further research is needed to determine whether this directly affects sterility in men. Sheynkin, Y.; Jung M;Yoo P;Schulsinger D;Komaroff E (2004-12-9). "Increase in scrotal temperature in laptop computer users". Human Reproduction 20 (2): 452-5. Epub. Retrieved on 2006-12-14. A common practical solution to this problem is to place the laptop on a table or desk.
Heat from using laptop on lap can also cause skin discoloration on the thighs. Levinbook, WS.; Mallet J; Grant-Kels JM (2007 Oct). "Laptop computer--associated erythema ab igne.". Cutis 80 (4): 319-20. Quadrant HealthCom. Retrieved on 2008-2-19.
Because of their small keyboard and trackpad pointing devices, the use of laptops can cause RSI, and for this reason laptops have docks that are used with ergonomic keyboards to prevent injury. The integrated screen often causes users to hunch over for a better view, which can cause neck or spinal injuries. Some health standards require that ergonomic keyboards be used in workplaces.
Laptops are generally prized targets of theft, and theft of laptops can lead to more serious problems such as identity theft from stolen credit card numbers.TuxMobil\'s page with a list of information and protection devices Most laptops have a Kensington security slot to chain the computer to a desk with a third party security cable. In addition to this, modern operating systems and software may have disk encryption functionality that renders the data on the laptop\'s hard drive unreadable without a key.
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