Glossary - L

Laptop

Laptop (defined as a computer we can work on our lap), sometimes called a notebook, is generally a portable computer. The first idea of creating a portable computer came in the early 1970’s by Alan Kay at Xerox® PARC described in his 1972 paper as the "Dynabook". Since then laptops have dramatically changed, today we use laptops to perform the same activities and work as we do on desktop computers. Laptop components are size and weight optimized, and designed for low power consumption.  Laptops use an LCD display, a thin (Slim) DVD drive, standard RAM SO-DIMM module, a "mobile" optimized power consumption processor, a touchpad and slim type keyboard. There is no price difference between today’s desktop and laptop, and therefore significantly increasing the interest of the laptops for their portability.  On March 2011, Lenovo® introduced the first eye-controlled laptop using an eye tracking technology built in to a small infrared camera.  The eye's position is tracked to perform the select, point, and scroll functions similar to a mouse.

Linux®

Linux® is a Unix®-based operating system (originally just for the core). The Linux® operating system is popular for its distributions that are easy to install or use directly (Live CD). Linux® is free software, so it can be modified and distributed (copied, shared) freely. This distinguishes it from proprietary systems (e.g. Microsoft Windows® or Mac OS® X) for which the user has to pay and follow restrictive licensing parameters.

Linus Torvalds began developing the Linux® kernel in 1991 as a hobby. The Unix® operating system favors simplicity and is used at universities. The first version of the Linux® kernel (0.01) was published on the Internet on September 17, 1991. Linus is still the head of core development, which publishes Linux® Kernel Archives at kernel.org. Even though a new version has been released, some older versions are still maintained by other programmers. Programmers from all around the world collaborate on the project. The development of the core is largely funded by companies like Red Hat®, Intel®, IBM® and others. The logo and mascot of the Linux® operating system is a penguin called Tux, based on an image created by Larry Ewing in 1996.

Linux is open source software, meaning that the source code is available to be modified and redistributed in compliance with certain conditions. Various open source software licenses are now being used to protect against source code abuse. The Linux® kernel itself is protected and distributed under GPLv2.

Liquid crystal display (LCD)

LCD is short for Liquid Crystal Display, a flat electronic visual display that uses the liquid crystals which do not emit light directly. They are used in a wide range of devices and facilities, including computer monitors, television, instrument panels, aircraft cockpit displays, mobile phones, video players, gaming devices, clocks, watches, calculators, and telephones. LCDs have replaced cathode ray tube (CRT) displays in most applications. They are usually more compact, lightweight, portable, less expensive, more reliable, and easier on the eyes and since they do not use phosphors, they cannot suffer image burn-in. LCDs are more energy efficient and offer safer disposal than CRTs. Their low electrical power consumption enable their use in battery-powered electronic equipment. By 2008, worldwide sales of televisions with LCD screens had surpassed the sale of CRT units.

Loyaltyware

Loyaltyware is a sub-form of adware. Loyaltyware is a type of software that works around the concept of user loyalty by providing incentives in the form of cash, points, airline miles, or other type of goods while shopping.

LPT (IEEE 1284)

IEEE 1284 is a standard that defines a parallel interface for bi-directional data transfer between computers and peripherals (printers, faxes, scanners, disks, etc.).  The parallel interface was pioneered by Centronics© Data Computer Corporation in the 1970s. The Centronics© parallel interface was eventually replaced by the IEEE 1284 standard, which was officially adopted in 1994.  The IEEE 1284 standard defines the electrical characteristics of interface protocols for the use of hardware and associated cables. At a higher level, the software protocols refer to the relevant sub-standards. Parts of protocol sub-standards are independent from the hardware interface, unlike the parallel interface (e.g., USB).