KDE is an international free software community developing Free and Open Source software. As a central development hub, it provides tools and resources that allow collaborative work on this kind of software. Well-known products include the Plasma Desktop, KDE Frameworks and a range of cross-platform applications like Krita or digikam designed to run on Unix and Unix-like desktops, Microsoft Windows and Android. Being one of KDE's most recognized projects, the Plasma Desktop is the official / default desktop environment on many Linux distributions, such as openSUSE, Mageia, OpenMandriva, Kubuntu, KaOS and PCLinuxOS; the KDE community and its work can be measured in the following figures: KDE is one of the largest active Free Software communities. More than 2500 contributors participate in developing KDE software. About 20 new developers contribute their first code each month. KDE software consists of over 6 million lines of code. KDE software has been translated into over 108 languages. KDE software is available on more than 114 official FTP mirrors in over 34 countries.
A read-only mirror of all repositories can be found on Github. There are many free software projects maintained by the KDE community; the project known as KDE or KDE SC nowadays consists of three parts: KDE Plasma, a platform UI that provides the base for different workspaces like Plasma Desktop or Plasma Mobile KDE Frameworks, a collection of more than 70 free-to-use libraries built on top of Qt KDE Applications KDE Plasma is a user interface technology that can be adjusted to run on various form factors like desktops, netbooks and smartphones or embedded devices. The brand Plasma for the graphical workspaces has been introduced from KDE SC 4.4 onwards. During the fourth series there have been two additional workspaces besides the Plasma 4 Desktop called Plasma Netbook and Plasma Active; the latest KDE Plasma 5 features the following workspaces: Plasma Desktop for any mouse or keyboard driven computing devices like desktops or laptops Plasma Mobile for smartphones Plasma Minishell for embedded and touch-enabled devices, like IoT or automotive Plasma Media Center for TVs and set-top boxes KDE Frameworks provide more than 70 free and open-source libraries built on top of Qt.
Starting with Qt 5, this platform was transformed into a set of modules, now referred to as KDE Frameworks. These modules include: Solid, Phonon, etc. and are licensed either under the LGPL, BSD license, MIT License or X11 license. KDE Applications is a bundle of software, part of the official KDE Applications release. Like Okular, Dolphin or KDEnlive, they are built on KDE Frameworks and released on a 4 months schedule with the version numbering consisting of YY. MM. Software, not part of the official KDE Applications bundle can be found in the "Extragear" section, they feature their own versioning numbers. There are many standalone applications like KTorrent, Krita or Amarok that are designed to be portable between operating systems and deployable independent of a particular workspace or desktop environment; some brands consist of multiple applications, such as KDE Kontact. KDE neon is a software repository, it aims to provide the users with updated Qt and KDE software, while updating the rest of the OS components from the Ubuntu repositories at the normal pace.
KDE maintains that it is not a "KDE distribution," but rather an up-to-date archive of KDE and Qt packages. There is two "Developer" editions of KDE Neon. WikiToLearn, abbreviated WTL, is one of KDE's newer endeavors, it is a wiki that provides a platform to share open source textbooks. The idea is to have a massive library of textbooks for anyone and everyone to create, its roots lay in University of Milan, where a group of physics majors wanted to share notes—then decided that it was for everyone and not just their internal friend group. They have become an official KDE project with several universities backing it. Like many free/open source projects, developing KDE software is a volunteer effort, although various companies, such as Novell, Nokia, or Blue Systems employ or employed developers to work on various parts of the project. Since a large number of individuals contribute to KDE in various ways (e.g. code
KDE Software Compilation
The KDE Software Compilation was an umbrella term for the desktop environment plus a range of included applications produced by KDE. From its 1.0 release in July 1998 until the release of version 4.4 in February 2010, the Software Compilation was known as KDE, which stood for K Desktop Environment until the rebrand. The called KDE SC was used for all releases from 4.4 onward until the final release 4.14 in July 2014. It consisted of the KDE Plasma 4 desktop and those KDE applications, whose development teams chose to follow the Software Compilation's release schedule. After that, the KDE SC was split into three separate product entities: KDE Plasma, KDE Frameworks and KDE Applications, each with their own independent release schedules. KDE was founded in 1996 by Matthias Ettrich, a student at the Eberhard Karls University of Tübingen. At the time, he was troubled by certain aspects of the Unix desktop. Among his qualms was that none of the applications looked, felt, or worked alike, he proposed the formation of not only a set of applications, rather, a desktop environment, in which users could expect things to look and work consistently.
He wanted to make this desktop easy to use. His initial Usenet post spurred a lot of interest, the KDE project was born. Ettrich chose to use Trolltech's Qt framework for the KDE project. Other programmers started developing KDE/Qt applications, by early 1997, a few applications were being released. On 12 July 1998, K Desktop Environment 1.0 was released. In November 1998, the Qt toolkit was dual-licensed under the free/open source Q Public License and a proprietary license for proprietary software developers. Debate continued about compatibility with the GNU General Public License, so in September 2000, Trolltech made the Unix version of the Qt libraries available under the GPL, in addition to the QPL. Trolltech continued to require licenses for developing proprietary software with Qt; the core libraries of KDE are collectively licensed under the GNU LGPL, but the only way for proprietary software to make use of them was to be developed under the terms of the Qt proprietary license. Beginning 23 October 2000, the second series of releases, K Desktop Environment 2, introduced significant technological improvements.
These included DCOP, KIO, KParts, KHTML. The third series was much larger than previous series, consisting of six major releases starting on 3 April 2002; the API changes between K Desktop Environment 2 and K Desktop Environment 3 were comparatively minor, meaning that the KDE 3 can be seen as a continuation of the K Desktop Environment 2 series. All releases of K Desktop Environment 3 were built upon Qt 3, only released under the GPL for Linux and Unix-like operating systems, including Mac OS X, it is marked stable running on Mac OS X since 2008. Unlike KDE SC 4, however, it requires an X11 server to operate. In 2002, members of the KDE on Cygwin project began porting the GPL licensed Qt/X11 code base to Windows. KDE Software Compilation 4, first released on 11 January 2008, is based on Qt 4, released under the GPL for Windows and Mac OS X. Therefore, KDE SC 4 applications can be compiled and run natively on these operating systems as well. KDE Software Compilation 4 on Mac OS X is considered beta, while on Windows it is not in the final state, so applications can be unsuitable for day to day use.
KDE SC 4 includes technical changes. The centerpiece is a redesigned desktop and panels collectively called Plasma, which replaces Kicker, KDesktop, SuperKaramba by integrating their functionality into one piece of technology. There are a number of new frameworks, including Phonon Solid, Decibel. Featured is a metadata and search framework, incorporating Strigi as a full-text file indexing service, NEPOMUK with KDE integration. Starting with Qt 4.5, Qt was made available under the LGPL version 2.1, a major step for KDE adoption in corporate and proprietary environments, as the LGPL permits proprietary applications to link to libraries licensed under the LGPL. As of August 2014, KDE no longer provides synchronized releases of the entire software compilation. Major changes include a move from Qt 4 to Qt 5, support for the next-generation display server protocol Wayland, support for the next-generation rendering API Vulkan and modularization of the KDE core libraries. Initial releases of Frameworks 5 and Plasma 5 were made available in July 2014.
KDE SC releases are made to the KDE FTP server in the form of source code with configure scripts, which are compiled by operating system vendors and integrated with the rest of their systems before distribution. Most vendors use only stable and tested ve
A formula editor is a name for a computer program, used to typeset mathematical works or formulae. Formula editors serve two purposes: They allow word processing and publication of technical content either for print publication, or to generate raster images for web pages or screen presentations, they provide a means for users to specify input to computational systems, easier to read and check than plain text input and output from computational systems, easy to understand or ready for publication. Content for formula editors can be provided manually using e.g.. TeX or MathML, via a point-and-click GUI, or as computer generated results from symbolic computations such as Mathematica. Typical features include the ability to nest fractions, superscripts, subscripts and underscripts together with special characters such as mathematical symbols and scalable parentheses; some systems are capable of re-formatting formulae into simpler forms or to adjust line-breaking automatically, while preserving the mathematical meaning of a formula.
TeX, a typesetting system designed and written by Donald Knuth LaTeX, a document markup language and document preparation system for the TeX typesetting program MathML, an application of XML for describing mathematical notations and capturing both its structure and content. It aims at integrating mathematical formulae into World Wide Web pages and other documents, it is a recommendation of the W3C math working group
GCompris is a software suite comprising educational entertainment software for children aged 2 to 10. GCompris was written in C and Python using the GTK+ widget toolkit, but a rewrite in C++ and QML using the Qt widget toolkit is since early 2014 in process. GCompris is free and open-source software subject to the requirements of the GNU General Public License version 3 and has been part of the GNU project; the name GCompris is a pun, in the French language is pronounced the same as the phrase "I have understood", J'ai compris. It is available for macOS and Windows. Binaries compiled for Microsoft Windows and macOS are distributed with a restricted number of activities. At the time of writing GCompris comprised more than 130 games, called "activities"; these are bundled into the following groups: Computer discovery: keyboard, different mouse gestures Numeracy: table memory, double entry table, mirror images Science: the canal lock, the water cycle, the submarine, electric simulations Geography: place the country on the map Games: chess, connect 4, sudoku Reading: reading practice Other: learn to tell time, puzzle of famous paintings, vector drawing, cartoon making The first version of the game was made in 2000 by Bruno Coudoin, a French software engineer.
An operating system is system software that manages computer hardware and software resources and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may include accounting software for cost allocation of processor time, mass storage and other resources. For hardware functions such as input and output and memory allocation, the operating system acts as an intermediary between programs and the computer hardware, although the application code is executed directly by the hardware and makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer – from cellular phones and video game consoles to web servers and supercomputers; the dominant desktop operating system is Microsoft Windows with a market share of around 82.74%. MacOS by Apple Inc. is in second place, the varieties of Linux are collectively in third place. In the mobile sector, use in 2017 is up to 70% of Google's Android and according to third quarter 2016 data, Android on smartphones is dominant with 87.5 percent and a growth rate 10.3 percent per year, followed by Apple's iOS with 12.1 percent and a per year decrease in market share of 5.2 percent, while other operating systems amount to just 0.3 percent.
Linux distributions are dominant in supercomputing sectors. Other specialized classes of operating systems, such as embedded and real-time systems, exist for many applications. A single-tasking system can only run one program at a time, while a multi-tasking operating system allows more than one program to be running in concurrency; this is achieved by time-sharing, where the available processor time is divided between multiple processes. These processes are each interrupted in time slices by a task-scheduling subsystem of the operating system. Multi-tasking may be characterized in co-operative types. In preemptive multitasking, the operating system slices the CPU time and dedicates a slot to each of the programs. Unix-like operating systems, such as Solaris and Linux—as well as non-Unix-like, such as AmigaOS—support preemptive multitasking. Cooperative multitasking is achieved by relying on each process to provide time to the other processes in a defined manner. 16-bit versions of Microsoft Windows used cooperative multi-tasking.
32-bit versions of both Windows NT and Win9x, used preemptive multi-tasking. Single-user operating systems have no facilities to distinguish users, but may allow multiple programs to run in tandem. A multi-user operating system extends the basic concept of multi-tasking with facilities that identify processes and resources, such as disk space, belonging to multiple users, the system permits multiple users to interact with the system at the same time. Time-sharing operating systems schedule tasks for efficient use of the system and may include accounting software for cost allocation of processor time, mass storage and other resources to multiple users. A distributed operating system manages a group of distinct computers and makes them appear to be a single computer; the development of networked computers that could be linked and communicate with each other gave rise to distributed computing. Distributed computations are carried out on more than one machine; when computers in a group work in cooperation, they form a distributed system.
In an OS, distributed and cloud computing context, templating refers to creating a single virtual machine image as a guest operating system saving it as a tool for multiple running virtual machines. The technique is used both in virtualization and cloud computing management, is common in large server warehouses. Embedded operating systems are designed to be used in embedded computer systems, they are designed to operate on small machines like PDAs with less autonomy. They are able to operate with a limited number of resources, they are compact and efficient by design. Windows CE and Minix 3 are some examples of embedded operating systems. A real-time operating system is an operating system that guarantees to process events or data by a specific moment in time. A real-time operating system may be single- or multi-tasking, but when multitasking, it uses specialized scheduling algorithms so that a deterministic nature of behavior is achieved. An event-driven system switches between tasks based on their priorities or external events while time-sharing operating systems switch tasks based on clock interrupts.
A library operating system is one in which the services that a typical operating system provides, such as networking, are provided in the form of libraries and composed with the application and configuration code to construct a unikernel: a specialized, single address space, machine image that can be deployed to cloud or embedded environments. Early computers were built to perform a series of single tasks, like a calculator. Basic operating system features were developed in the 1950s, such as resident monitor functions that could automatically run different programs in succession to speed up processing. Operating systems did not exist in their more complex forms until the early 1960s. Hardware features were added, that enabled use of runtime libraries and parallel processing; when personal computers became popular in the 1980s, operating systems were made for them similar in concept to those used on larger computers. In the 1940s, the earliest electronic digital systems had no operating systems.
Electronic systems of this time were programmed on rows of mechanical switches or by jumper wires on plug boards. These were special-purpose systems that, for example, generated ballistics tables for the military or controlled the pri
Microsoft Windows is a group of several graphical operating system families, all of which are developed and sold by Microsoft. Each family caters to a certain sector of the computing industry. Active Windows families include Windows Embedded. Defunct Windows families include Windows Mobile and Windows Phone. Microsoft introduced an operating environment named Windows on November 20, 1985, as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces. Microsoft Windows came to dominate the world's personal computer market with over 90% market share, overtaking Mac OS, introduced in 1984. Apple came to see Windows as an unfair encroachment on their innovation in GUI development as implemented on products such as the Lisa and Macintosh. On PCs, Windows is still the most popular operating system. However, in 2014, Microsoft admitted losing the majority of the overall operating system market to Android, because of the massive growth in sales of Android smartphones.
In 2014, the number of Windows devices sold was less than 25 %. This comparison however may not be relevant, as the two operating systems traditionally target different platforms. Still, numbers for server use of Windows show one third market share, similar to that for end user use; as of October 2018, the most recent version of Windows for PCs, tablets and embedded devices is Windows 10. The most recent versions for server computers is Windows Server 2019. A specialized version of Windows runs on the Xbox One video game console. Microsoft, the developer of Windows, has registered several trademarks, each of which denote a family of Windows operating systems that target a specific sector of the computing industry; as of 2014, the following Windows families are being developed: Windows NT: Started as a family of operating systems with Windows NT 3.1, an operating system for server computers and workstations. It now consists of three operating system subfamilies that are released at the same time and share the same kernel: Windows: The operating system for mainstream personal computers and smartphones.
The latest version is Windows 10. The main competitor of this family is macOS by Apple for personal computers and Android for mobile devices. Windows Server: The operating system for server computers; the latest version is Windows Server 2019. Unlike its client sibling, it has adopted a strong naming scheme; the main competitor of this family is Linux. Windows PE: A lightweight version of its Windows sibling, meant to operate as a live operating system, used for installing Windows on bare-metal computers, recovery or troubleshooting purposes; the latest version is Windows PE 10. Windows IoT: Initially, Microsoft developed Windows CE as a general-purpose operating system for every device, too resource-limited to be called a full-fledged computer. However, Windows CE was renamed Windows Embedded Compact and was folded under Windows Compact trademark which consists of Windows Embedded Industry, Windows Embedded Professional, Windows Embedded Standard, Windows Embedded Handheld and Windows Embedded Automotive.
The following Windows families are no longer being developed: Windows 9x: An operating system that targeted consumers market. Discontinued because of suboptimal performance. Microsoft now caters to the consumer market with Windows NT. Windows Mobile: The predecessor to Windows Phone, it was a mobile phone operating system; the first version was called Pocket PC 2000. The last version is Windows Mobile 6.5. Windows Phone: An operating system sold only to manufacturers of smartphones; the first version was Windows Phone 7, followed by Windows Phone 8, the last version Windows Phone 8.1. It was succeeded by Windows 10 Mobile; the term Windows collectively describes any or all of several generations of Microsoft operating system products. These products are categorized as follows: The history of Windows dates back to 1981, when Microsoft started work on a program called "Interface Manager", it was announced in November 1983 under the name "Windows", but Windows 1.0 was not released until November 1985.
Windows 1.0 was to achieved little popularity. Windows 1.0 is not a complete operating system. The shell of Windows 1.0 is a program known as the MS-DOS Executive. Components included Calculator, Cardfile, Clipboard viewer, Control Panel, Paint, Reversi and Write. Windows 1.0 does not allow overlapping windows. Instead all windows are tiled. Only modal dialog boxes may appear over other windows. Microsoft sold as included Windows Development libraries with the C development environment, which included numerous windows samples. Windows 2.0 was released in December 1987, was more popular than its predecessor. It features several improvements to the user memory management. Windows 2.03 changed the OS from tiled windows to overlapping windows. The result of this change led to Apple Computer filing a suit against Microsoft alleging infringement on Apple's copyrights. Windows 2.0
WYSIWYG is an acronym for "what you see is what you get". In computing, a WYSIWYG editor is a system in which content can be edited in a form resembling its appearance when printed or displayed as a finished product, such as a printed document, web page, or slide presentation. WYSIWYG implies a user interface that allows the user to view something similar to the end result while the document is being created. In general, WYSIWYG implies the ability to directly manipulate the layout of a document without having to type or remember names of layout commands; the actual meaning depends on the user's perspective, e.g. In presentation programs, compound documents, web pages, WYSIWYG means the display represents the appearance of the page displayed to the end-user, but does not reflect how the page will be printed unless the printer is matched to the editing program, as it was with the Xerox Star and early versions of the Apple Macintosh. In word processing and desktop publishing applications, WYSIWYG means that the display simulates the appearance and represents the effect of fonts and line breaks on the final pagination using a specific printer configuration, so that, for example, a citation on page 1 of a 500-page document can refer to a reference three hundred pages later.
WYSIWYG describes ways to manipulate 3D models in stereo-chemistry, computer-aided design, 3D computer graphics. Modern software does a good job of optimizing the screen display for a particular type of output. For example, a word processor is optimized for output to a typical printer; the software emulates the resolution of the printer in order to get as close as possible to WYSIWYG. However, not the main attraction of WYSIWYG, the ability of the user to be able to visualize what they are producing. In many situations, the subtle differences between what the user sees and what the user gets are unimportant. In fact, applications may offer multiple WYSIWYG modes with different levels of "realism", including A composition mode, in which the user sees something somewhat similar to the end result, but with additional information useful while composing, such as section breaks and non-printing characters, uses a layout, more conducive to composing than to layout. A layout mode, in which the user sees something similar to the end result, but with some additional information useful in ensuring that elements are properly aligned and spaced, such as margin lines.
A preview mode, in which the application attempts to present a representation, as close to the final result as possible. Before the adoption of WYSIWYG techniques, text appeared in editors using the system standard typeface and style with little indication of layout. Users were required to enter special non-printing control codes to indicate that some text should be in boldface, italics, or a different typeface or size. In this environment there was little distinction between text editors and word processors; these applications used an arbitrary markup language to define the codes/tags. Each program had its own special way to format a document, it was a difficult and time-consuming process to change from one word processor to another; the use of markup tags and codes remains popular today in some applications due to their ability to store complex formatting information. When the tags are made visible in the editor, they occupy space in the unformatted text and so disrupt the desired layout and flow.
Bravo, a document preparation program for the Alto produced at Xerox PARC by Butler Lampson, Charles Simonyi and colleagues in 1974, is considered the first program to incorporate WYSIWYG technology, displaying text with formatting. The Alto monitor was designed so that one full page of text could be seen and printed on the first laser printers; when the text was laid out on the screen, 72 PPI font metric files were used, but when printed 300 PPI files were used—thus one would find characters and words off, a problem that continues to this day. Bravo was released commercially and the software included in the Xerox Star can be seen as a direct descendant of it. In parallel with but independent of the work at Xerox PARC, Hewlett Packard developed and released in late 1978 the first commercial WYSIWYG software application for producing overhead slides or what today are called presentation graphics; the first release, named BRUNO, ran on the HP 1000 minicomputer taking advantage of HP's first bitmapped computer terminal the HP 2640.
BRUNO was ported to the HP-3000 and re-released as "HP Draw". By 1981 MicroPro advertised that its WordStar word processor had WYSIWYG, but its display was limited to displaying styled text in WYSIWYG fashion. In 1983 the Weekly Reader advertised its Stickybear educational software with the slogan "what you see is what you get", with photographs of its Apple II graphics, but home computers of the 1970s and early 1980s lacked the sophisticated graphics capabilities necessary to display WYSIWYG documents, meaning that such applications were confined to limited-purpose, high-end workstations that were too expensive for the general public to afford. Towards the mid-1980s, things began to change. Improving technology allowed the production of cheaper bitmapped displays, WYSIWYG software started to appear for more popular computers, including LisaWrite