Glossary/fi: Difference between revisions

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This page sets out to provide a non-technical reference, together with links for further information or demonstration. See also [[Special:myLanguage/Jargon File|Jargon File]].
This page sets out to provide a non-technical reference, together with links for further information or demonstration. See also [[Special:myLanguage/Jargon File|Jargon File]].
==A General Overview==
[http://www.kde.org/announcements/4.0/desktop.php A KDE 4.0 Visual Guide:] and a [http://media.ereslibre.es/2008/06/kde41.ogg 4.1 screencast] gives an excellent overview of '''KDE Software Compilation 4''' in the early days.
The following glossary is intended to help you find your way through the mists of new names and new concepts.  In some cases you can find a link from a '''KDE 3''' component to its equivalent in the context of '''KDE SC 4''' software.
<span id="Activities"></span>
<span id="Activities"></span>
===Activities===
===Activities===
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''More info'':  
''More info'':  
:[[Special:myLanguage/Plasma/FAQ/4.3#How can I add/remove an activity?|Creating Activities]]
:[[Special:myLanguage/Plasma#Activities|Creating Activities]]
<span id="Akonadi"></span>
<span id="Akonadi"></span>
===Akonadi===
===Akonadi===
:The data storage access mechanism for all ''PIM'' (Personal Information Manager) data in ''KDE SC 4''.  One single storage and retrieval system allows efficiency and extensibility not possible under ''KDE 3'', where each PIM component had its own system. Note that use of '''Akonadi''' does not change data storage formats (''vcard'', ''iCalendar'', ''mbox'', ''maildir'' etc.) - it just provides a new way of accessing and updating the data.
:The data storage access mechanism for all ''PIM'' (Personal Information Manager) data in ''KDE''.  This allows various applications to access the required information in one place. Note that use of '''Akonadi''' does not change data storage formats (''vcard'', ''iCalendar'', ''mbox'', ''maildir'' etc.) - it just provides a new way of accessing and updating the data.


:The main reasons for design and development of '''Akonadi''' are of technical nature, e.g. having a unique way to access PIM-data (contacts, calendars, emails..) from different applications (e.g. '''kmail''', '''kword'''..), thus eliminating the need to write similar code here and there.
:The main reasons for design and development of '''Akonadi''' are of technical nature, e.g. having a unique way to access PIM-data (contacts, calendars, emails..) from different applications (e.g. '''kmail''', '''kword'''..), thus eliminating the need to write similar code here and there.
Line 32: Line 26:
:[http://en.wikipedia.org/wiki/Akonadi Wikipedia - Akonadi]  
:[http://en.wikipedia.org/wiki/Akonadi Wikipedia - Akonadi]  
:[http://techbase.kde.org/Projects/PIM/Akonadi Techbase - Akonadi]
:[http://techbase.kde.org/Projects/PIM/Akonadi Techbase - Akonadi]
<span id="aRts"></span>
===aRts===
:The sound framework in KDE 2 and 3.  Its single-tasking nature caused problems when two sources of sound were encountered.  In the ''Plasma workspace'' it is replaced by [[#Phonon|Phonon]]
''More info'':
:[http://en.wikipedia.org/wiki/ARts Wikipedia - aRts]
:[http://www.arts-project.org/gen/newsarchive/news_2000.html aRts Home Page]
<span id="Containment"></span>
<span id="Containment"></span>
===Baloo===
===Baloo===
:'''Baloo''' replaced [[Special:myLanguage/Glossary#Nepomuk|Nepomuk]] as a "sematic desktop" search framework. [[Special:myLanguage/Baloo|Baloo]] is a file indexing and search service that '''Dolphin''' uses to search for files. In a terminal type, <code>balooctl check</code> to find out whether an index was created already. <code>balooctl disable</code> and <code>balooctl status</code> are helpful instructions as well.
[[Special:myLanguage/Baloo|Baloo]] is a file indexing and search service that '''Dolphin''' and '''Elisa''' use to get metadata for files and to allow global searches. In a terminal type, <code>balooctl check</code> to find out whether an index was created already. <code>balooctl disable</code> and <code>balooctl status</code> are helpful instructions as well.


''More info'':
''More info'':
Line 52: Line 39:
<span id="D-Bus"></span>
<span id="D-Bus"></span>
===D-Bus===
===D-Bus===
:An inter-service messaging system. Developed by Red Hat<sup>®</sup>, it was heavily influenced by KDE3's ''DCOP'', which it supersedes.
:An inter-service messaging system. D-Bus allows multiple programs to interact. Developed by Red Hat<sup>®</sup>, it was heavily influenced by KDE3's ''DCOP'', which it supersedes.


''More info'':
''More info'':
Line 59: Line 46:
<span id="Dolphin"></span>
<span id="Dolphin"></span>
===Dolphin===
===Dolphin===
:The default file manager in KDE SC 4.  It has a side panel (''Places''), but navigation is mainly by the ''breadcrumb'' trail above the main window. Split windows are possible, and views can be applied to individual windows. Mounting and umounting USB devices can be done in the side-panel. Other directories can be added to the Places panel.  A ''Tree view'' is also possible.
:The default file manager in KDE Plasma.  It has a side panel (''Places''), but navigation is mainly by the ''breadcrumb'' trail above the main window. It has various advanced features such as split windows and individual views in different windows. Mounting and umounting USB devices can be done in the side-panel. Other directories can be added to the Places panel.  A ''Tree view'' is also possible.


''More info'':
''More info'':
:[http://en.wikipedia.org/wiki/Dolphin_(software) Wikipedia - Dolphin (software)]
:[http://en.wikipedia.org/wiki/Dolphin_(software) Wikipedia - Dolphin (software)]
:[http://dot.kde.org/2007/03/01/road-kde-4-dolphin-and-konqueror Road to KDE 4: Dolphin and Konqueror]
:[http://arstechnica.com/news.ars/post/20070405-afirst-look-at-dolphin-the-kde-4-file-manager.html Ars Technica: A First Look at Dolphin]
:[http://www.youtube.com/watch?v=i4HS1v0a9Xs Youtube - KDE 4 rev 680445 - Dolphin]
:[http://introducingkde4.blogspot.com/2007/12/dolphin.html Introducing KDE 4 Blog - Dolphin]
:[[Tutorials/File_Management|The UserBase File Management Tutorial]]
:[[Tutorials/File_Management|The UserBase File Management Tutorial]]
<span id="Extender"></span>
===Extender===
:''Extenders'' are a special kind of popup that can grow out of a [[#Plasma|Plasma]] panel for example. Extenders have detachable parts. Extenders are a new concept that arrived in Plasma for KDE 4.2. Notifications already use this system. This enables, for example, a user to drag a notification of a download or file copy job, onto his or her desktop and keep track of it there. The same can be done for other kinds of notifications, too.
''More info'':
:[http://kde-look.org/content/show.php/KDE+Extender+Mockup?content=30012 Mockup Screenshots]
:[http://plasma.kde.org/cms/1069 The Elements of Plasma]
<span id="Flake"></span>
<span id="Flake"></span>
===Flake===
===Flake===
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''More info'':
''More info'':
:[http://ghns.freedesktop.org Home of GHNS]
:[http://store.kde.org The KDE Store]
:[http://lwn.net/Articles/227855/ An article on GHNS in KDE SC 4]
<span id="Home Directory"></span>
<span id="Home Directory"></span>
===Home Directory===
===Home Directory===
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''More info'':
''More info'':
:[http://en.wikipedia.org/wiki/Home_directory Wikipedia - Home directory]  
:[http://en.wikipedia.org/wiki/Home_directory Wikipedia - Home directory]  
<span id="KControl"></span>
===KControl===
:''KDE Control Center'', for setting global preferences in KDE 3. Replaced by the [[#System Settings|System Settings]] interface in KDE SC 4.
<span id="KDOM"></span>
===KDOM===
:A [[#KPart|''KPart'']] module making ''KHTML DOM (Document Object Model) '' rendering capabilities available to all applications. [[#KSVG|KSVG2]] is built on KDOM for KDE SC 4.
<span id="KHTML"></span>
<span id="KHTML"></span>
===KHTML===
===KHTML===
:''KHTML'' is the HTML rendering engine for the KDE Plasma desktop, as used by the '''Konqueror''' browser. It also provides a KPart that enables all KDE applications to display web content. A new introduction, ''Qt WebKit'' is also for Plasma and other application development.
:''KHTML'' is a HTML rendering engine that was the base of WebKit, the engine that powers many browsers still in use today (e.g. Safari).  
<span id="Kicker"></span>
===Kicker===
:In KDE 3, the relocatable bar, usually at the bottom of the screen (sometimes called the [[#Panel|''Panel'']]), on which application launchers, the [[#Pager|Pager]], and buttons for running applications reside. See [[#Panel|Panel]]
<span id="Kickoff"></span>
<span id="Kickoff"></span>
===Kickoff===
===Kickoff===
:In KDE SC 4 (and some late versions of KDE 3), a launch menu in which apps are sorted by functional group. "Favorites" replaces the "Most used applications" in ''Classic Menu'', and applications can be added to it.  Right-click also offers the possibility of adding applications to the desktop or panel. Rapid access to a less-used application is made possible with the search box. Other menus are being worked on, since KDE SC 4 can be used with more than one launcher, should that be required.  
:Kickoff is a launch menu in KDE Plasma in which apps are sorted by functional groups. Right-click also offers the possibility of adding applications to the desktop or panel. Rapid access to a less-used application is made possible with the search box. There are also alternatives, such as the fullscreen app dashboard.  


''More info'':
''More info'':
:[http://home.kde.org/~binner/kickoff/sneak_preview.html Kickoff Sneak Preview]
:[http://en.opensuse.org/Kickoff Design documentation]
:[http://en.opensuse.org/Kickoff Design documentation]
<span id="KJS"></span>
<span id="KJS"></span>
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<span id="KInfoCenter"></span>
<span id="KInfoCenter"></span>
===KInfoCenter===
===KInfoCenter===
:'''Kinfocenter''' originated as part of [[#KControl|KControl]] standing alone from KDE 3.1. In KDE SC 4 up until 4.4 it is replaced by modules configured in [[#System Settings|System Settings]], notably [[#Solid|Solid]], and is being reintroduced as an application in KDE SC 4.5.
:'''KInfoCenter''' originated as part of [[#KControl|KControl]] standing alone from KDE 3.1. It can display data about your system such as energy usage, hardware info and many more.


''More Info'':  
''More Info'':  
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:[http://en.wikipedia.org/wiki/KIO Wikipedia - KIO]  
:[http://en.wikipedia.org/wiki/KIO Wikipedia - KIO]  
:[http://www.linux.com/feature/124686 Linux.com - Master the KIO slaves]  
:[http://www.linux.com/feature/124686 Linux.com - Master the KIO slaves]  
:[http://osdir.com/Article2159.phtml Breaking the Network Barrier]
<span id="Kiosk"></span>
<span id="Kiosk"></span>
===Kiosk===
===Kiosk===
:[http://techbase.kde.org/KDE_System_Administration/Kiosk/Introduction Kiosk] is a framework for restricting user capabilities on a ''KDE platform'' system, ideal for use in locked-down environments such as Internet cafés. It is present in KDE 3 and KDE 4, but the administration tool, '''Kiosktool''' is KDE 3 only.  It can be used to configure KDE 4 apps, or '''kiosk''' configurations can be maintained by editing config files manually.
:[http://techbase.kde.org/KDE_System_Administration/Kiosk/Introduction Kiosk] is a framework for restricting user capabilities on a ''KDE platform'' system, ideal for use in locked-down environments such as Internet cafés. It has been unmaintained for quite some time now.
<span id="KPart"></span>
<span id="KPart"></span>
===KPart===
===KPart===
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<span id="KRunner"></span>
<span id="KRunner"></span>
===KRunner===
===KRunner===
:The mini-command-line that is accessed from the Classic menu, the keyboard shortcut ''Alt+F2'', or a right-click on the desktop. In '''KDE SC 4''' a partial name will display all possible matches
:The mini-command-line that is accessed from the Classic menu, the keyboard shortcut ''Alt+F2'', or a right-click on the desktop.


''More info'':
''More info'':
:[http://www.youtube.com/watch?v=B1-SFSmwTXw Youtube - KDE SC 4.1 KRunner]
:[[Special:myLanguage/Plasma/Krunner | KRunner wiki]
<span id="KSVG"></span>
 
===KSVG===
: ''KSVG'' enables support for ''scalable vector graphics'' in a [[#KHTML|KHTML]] browser.  ''KSVG2'' extends this for KDE SC 4.
<span id="KWin"></span>
<span id="KWin"></span>
===KWin===
===KWin===
:''KWin'' is the window manager. This is where window decorations can be changed and themes applied. KDE SC 4 extends KWin to provide support for ''3D Compositing effects'' on the desktop.
:''KWin'' is the window manager of KDE. This is where window decorations can be changed and themes applied.  


''More info'':
''More info'':
:[[Special:myLanguage/KWin|KWin]]
:[[Special:myLanguage/KWin|KWin]]
:[http://dot.kde.org/1180541665/ Road to KDE 4: KWin Composite]
:[http://francis.giannaros.org/blog/2007/12/03/kde4-desktop-effects-kwin-composite-video-tour/  KDE SC 4 Desktop Effects Video Tour]
:[http://www.youtube.com/watch?v=YrFz7IxXppU Youtube - KDE SC 4.0 KWin Composite Showcast]
:[http://www.youtube.com/watch?v=4WBLlc6xCQ4 Youtube - KWin compositing config &amp; intro]
<span id="Mini-CLI"></span>
===Mini-CLI===
:See [[#KRunner|KRunner]]
<span id="Nepomuk"></span>
===Nepomuk===
:"Networked Environment for Personalized, Ontology-based Management of Unified Knowledge",  ''Nepomuk'' aims to remove artificial barriers between information to allow dynamic classification, organisation and presentation of data to the user.  Whether downloaded from the internet, received in an email or scribbled in a note, information is globally searchable and tagged with intelligent data.  See [http://en.wikipedia.org/wiki/Semantic_desktop ''The Semantic Desktop''] for further discussion of this concept.
''More info'':
:[[Special:MyLanguage/Nepomuk|Userbase Nepomuk page]]
:[http://en.wikipedia.org/wiki/Semantic_desktop Wikipedia - Semantic Desktop]
:[http://en.wikipedia.org/wiki/NEPOMUK_(framework)  Wikipedia - NEPOMUK Framework]
:[http://nepomuk.semanticdesktop.org/xwiki/bin/view/Main1/ NEPOMUK website]
:[http://nepomuk.kde.org/discover/user NEPOMUK KDE]
<span id="Oxygen"></span>
===Oxygen===
:''Oxygen'' is the default theme of KDE SC 4. Designed to bring "a breath of fresh air" to the desktop by removing the simplistic, cartoonish icons, and replacing them with a clean theme and photo-realistic icons.  Oxygen uses a desaturated palette to avoid the icons becoming a distraction and uses detailed scalable graphics (SVG).
''More info'':
:[http://en.wikipedia.org/wiki/Oxygen_Project Wikipedia - Oxygen Project]
:[http://www.oxygen-icons.org/?cat=3 Oxygen Icons]
<span id="Pager"></span>
<span id="Pager"></span>
===Pager===
===Pager===
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<span id="Panel"></span>
<span id="Panel"></span>
===Panel===
===Panel===
:See [[#Kicker|Kicker]]. In '''KDE SC 4''' the name "kicker" is dropped, and the name "panel" is the norm.  "Applets"; are largely replaced by [[#Widget|Widgets]]
:See [[#Kicker|Kicker]]. In '''KDE Plasma''' the name "kicker" is dropped, and the name "panel" is the norm.  "Applets"; are largely replaced by [[#Widget|Widgets]]


''More info'':
''More info'':
Line 191: Line 129:
<span id="Phonon"></span>
<span id="Phonon"></span>
===Phonon===
===Phonon===
:A cross-platform multimedia API, interfacing with existing frameworks, such as ''gstreamer'' and ''xine engines''.  KDE 2 and 3 depended on ''aRts'' for sound.  ''Phonon'' replaces it.  
:A cross-platform multimedia API, interfacing with existing frameworks, such as ''gstreamer'' and ''xine engines''.


''More info'':
''More info'':
Line 199: Line 137:
<span id="Plasma"></span>
<span id="Plasma"></span>
===Plasma===
===Plasma===
:In KDE SC 4 the Plasma Desktop replaces ''KDesktop'', '''kicker''' and the ''superkaramba'' widget engine. The applets are called '''Plasmoids''', and range from informational widgets to mini-apps such as a calculator or dictionary. Widgets from other sources, such as ''SuperKaramba widgets'' or ''Google Gadgets'' are also supported.
:Plasma is the desktop environment from KDE. It is the part of the desktop that you can see. Plasma also acts as a glue between panels, plasmoids and Kickoff. Plasma Mobile allows Plasma to run on smartphones and uses the same underlying code base.


''More info'':
''More info'':
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:[[Special:myLanguage/Plasma|The Plasma main page]]
:[[Special:myLanguage/Plasma|The Plasma main page]]
:[[Special:myLanguage/Plasma/FAQ/Index|The Plasma FAQ's]]
:[[Special:myLanguage/Plasma/FAQ/Index|The Plasma FAQ's]]
:[http://www.youtube.com/watch?v=H5RpH9HOXJA&amp;feature=related  Youtube - Plasma Applets Galore (Part 1)]
:[http://liquidat.wordpress.com/ Liquidat&#039;s Blog]
<span id="Qt"></span>
<span id="Qt"></span>
===Qt===
===Qt===
:(Pronounced "cute") A framework/toolkit for writing cross-platform applications. It is used by many cross-platform applications such as '''Opera''' browser, '''GoogleEarth''' and '''Skype'''. ''Qt'' is developed by Trolltech, who are now part of the Nokia company.  Qt forms the underlying library KDE software is built on.  
:(Pronounced "cute") A framework/toolkit for writing cross-platform applications. It is used by many cross-platform applications such as '''Krita''', '''GoogleEarth''' and many others.  Qt forms the underlying library KDE software is built on.  


''More info'':
''More info'':
:[http://en.wikipedia.org/wiki/Qt_(toolkit) The Qt Toolkit]
:[http://en.wikipedia.org/wiki/Qt_(toolkit) The Qt Toolkit]
:[http://trolltech.com/products/qt/learnmore/demo Qt Demo Videos]
<span id="Solid"></span>
<span id="Solid"></span>
===Solid===
===Solid===
Line 221: Line 156:
''More info'':
''More info'':
:[http://solid.kde.org/cms/1058 Discover Solid]  
:[http://solid.kde.org/cms/1058 Discover Solid]  
:[http://dot.kde.org/1177385913/ Solid Brings Hardware Configuration and Control to the KDE platform]
<span id="Soprano"></span>
===Soprano===
:''Soprano'' is a sub-project of [[#Nepomuk|Nepomuk]], providing a repository for gathered information such as tags, ratings, etc..  This makes the information available to [[#Strigi|Strigi]]
''More info'':
:[http://liquidat.wordpress.com/2007/06/19/more-about-nepomuk-kde-soprano-and-kde-integration/ More about Nepomuk-KDE: Soprano and KDE platform integration]
<span id="Strigi"></span>
===Strigi===
:A deep-indexed search daemon, ''Strigi'' aims to be fast and light-weight.  It also uses ''SHA-1 hash'' which will help in the identification of duplicate files.
''More info'':
:[http://strigi.sourceforge.net/ Strigi - the fastest and smallest desktop searching program]
:[http://en.wikipedia.org/wiki/Strigi Wikipedia - Strigi]
<span id="System Settings"></span>
<span id="System Settings"></span>
===System Settings===
===System Settings===
:KDE SC 4 replacement for [[#KControl|KControl]] (Control Center) providing modular control over the KDE platform.  
:The system settings are the unified place where you can change and customize many aspects of the Plasma desktop and KWin such as icon themes, desktop effects and shortcuts.


''More info'':
''More info'':
:[[Special:myLanguage/System Settings|System Settings]]
:[[Special:myLanguage/System Settings|System Settings]]
:[http://www.lazytechguy.com/2008/01/kde4-system-settings.html KDE SC 4 System Settings illustrated]
<span id="Threadweaver"></span>
<span id="Threadweaver"></span>
===Threadweaver===
===Threadweaver===
:This thread programming library spreads work among multiple-core processors where available, prioritising them before queueing them for execution. ''ThreadWeaver'' provides a high-level job interface for multithreaded programming.  
:This thread programming library spreads work among multiple-core processors where available, prioritising them before queueing them for execution. ''ThreadWeaver'' provides a high-level job interface for multithreaded programming.  


''More info'':
''More info'':
Line 254: Line 173:
<span id="WebKit"></span>
<span id="WebKit"></span>
===WebKit===
===WebKit===
:HTML ''rendering engine'', originating from a fork of [[#KHTML|KHTML]]. Adopted by Apple and developed for Safari. ''Webkit'' brings the whole functionality back to KDE SC 4, where it is available through Qt.  
:HTML ''rendering engine'', originating from a fork of [[#KHTML|KHTML]]. Adopted by Apple and developed for Safari.  


''More info'':
''More info'':
Line 263: Line 182:
:Collins English Dictionary: "Any small mechanism or device the name of which is unknown or temporarily forgotten." In KDE software terms, a '''widget''' is a single component on the canvas. Other common names that are analogous are "applet" or "gadget". Superkaramba Themes, Apple's Dashboard, Google Gadgets, Yahoo Widgets, Vista Sidebar Widgets, Opera Widgets are all examples of other widget systems (some of which are supported by Plasma as well).
:Collins English Dictionary: "Any small mechanism or device the name of which is unknown or temporarily forgotten." In KDE software terms, a '''widget''' is a single component on the canvas. Other common names that are analogous are "applet" or "gadget". Superkaramba Themes, Apple's Dashboard, Google Gadgets, Yahoo Widgets, Vista Sidebar Widgets, Opera Widgets are all examples of other widget systems (some of which are supported by Plasma as well).
<span id="X-Server"></span>
<span id="X-Server"></span>
===X-Server===
===X Server===
:The ''X-Server'' represents a basic layer upon which the various GUIs like the KDE Plasma desktop are built. It manages the basic mouse and keyboard input (from the local host as well as from remote hosts) and provides elementary graphic routines to draw rectangles and other primitives.
:The ''X Server'' represents a basic layer upon which the various GUIs like the KDE Plasma desktop are built. It manages the basic mouse and keyboard input (from the local host as well as from remote hosts) and provides elementary graphic routines to draw rectangles and other primitives.
<span id="XMLGUI"></span>
<span id="XMLGUI"></span>
===XMLGUI===
===XMLGUI===
Line 272: Line 191:
:[http://en.wikipedia.org/wiki/XMLGUI Wikipedia - XMLGUI]  
:[http://en.wikipedia.org/wiki/XMLGUI Wikipedia - XMLGUI]  
:[http://en.wikipedia.org/wiki/Qt_Style_Sheets Wikipedia - Qt Style Sheets]
:[http://en.wikipedia.org/wiki/Qt_Style_Sheets Wikipedia - Qt Style Sheets]
<span id="ZUI"></span>
===ZUI===
:The "Zooming User Interface".  "By zooming out, users can get an overview of all the object groupings that they have made. These groupings may reflect the projects they are working on, be ways to keep different sets of files organized, etc. By hovering or clicking on one of these groups when zoomed out, users can either get a preview/snapshot of what is in the grouping, or zoom in on that grouping so that it is displayed full size on the physical screen." ''aseigo''.
''More info'':
:[http://www.youtube.com/watch?v=EhODrJkoidA Youtube ZUI demo]


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Revision as of 08:31, 8 July 2018

This page sets out to provide a non-technical reference, together with links for further information or demonstration. See also Jargon File.

Activities

Activities are sets of Plasma widgets that have their own wallpaper. A bit like Virtual Desktops, but not quite.
For example you have a "work activity" with commit rss feeds, a note with your TODO, a Folder View with your work related files, and a subtle wallpaper.
Next to it, you have your "freetime activity", with previews of family photos and dogs, rss feeds from your favourite blogs, a Folder View showing your movie collection, a twitter applet and of course that Iron Maiden wallpaper you have been loving since the early 80s.
At 1700 hours sharp you switch from the "work activity" to your "freetime activity".

More info:

Creating Activities

Akonadi

The data storage access mechanism for all PIM (Personal Information Manager) data in KDE. This allows various applications to access the required information in one place. Note that use of Akonadi does not change data storage formats (vcard, iCalendar, mbox, maildir etc.) - it just provides a new way of accessing and updating the data.
The main reasons for design and development of Akonadi are of technical nature, e.g. having a unique way to access PIM-data (contacts, calendars, emails..) from different applications (e.g. kmail, kword..), thus eliminating the need to write similar code here and there.
Another goal is to de-couple GUI applications like kmail from the direct access to external resources like mail-servers - which was a major reason for bug-reports/wishes with regard to performance/responsiveness in the past.

More info:

Akonadi for KDE's PIM
Wikipedia - Akonadi
Techbase - Akonadi

Baloo

Baloo is a file indexing and search service that Dolphin and Elisa use to get metadata for files and to allow global searches. In a terminal type, balooctl check to find out whether an index was created already. balooctl disable and balooctl status are helpful instructions as well.

More info:

Baloo

Containment

A Containment is a top level grouping of widgets. Each Containment manages the layout and configuration data of its set of widgets independently from other Containments.
The end result is that you can group widgets within a Containment according to the significance to your working pattern, rather than by directory grouping.

D-Bus

An inter-service messaging system. D-Bus allows multiple programs to interact. Developed by Red Hat®, it was heavily influenced by KDE3's DCOP, which it supersedes.

More info:

FreeDesktop.org: What is D-Bus?
Wikipedia: D-Bus

Dolphin

The default file manager in KDE Plasma. It has a side panel (Places), but navigation is mainly by the breadcrumb trail above the main window. It has various advanced features such as split windows and individual views in different windows. Mounting and umounting USB devices can be done in the side-panel. Other directories can be added to the Places panel. A Tree view is also possible.

More info:

Wikipedia - Dolphin (software)
The UserBase File Management Tutorial

Flake

Flake is a programming library to be used in KOffice and Calligra. Functionally, it provides Shapes to display content and Tools to manipulate content. Shapes can be zoomed or rotated and can be grouped to work as a single Shape, around which text flow is possible.

More info:

KDE Community Wiki - Flake

Get Hot New Stuff

Get Hot New Stuff (GHNS) is an open standard that makes it easy for users to download and install various extensions for their applications. Our implementation of GHNS is used by Plasma (for example to get new desktop themes), and by many applications and widgets.

More info:

The KDE Store

Home Directory

That's the place in your system where all your files are kept. You can write your files outside of this folder, but all applications are configured to propose this folder as place to write your files to. It is easier when you keep your things here.

More info:

Wikipedia - Home directory

KHTML

KHTML is a HTML rendering engine that was the base of WebKit, the engine that powers many browsers still in use today (e.g. Safari).

Kickoff

Kickoff is a launch menu in KDE Plasma in which apps are sorted by functional groups. Right-click also offers the possibility of adding applications to the desktop or panel. Rapid access to a less-used application is made possible with the search box. There are also alternatives, such as the fullscreen app dashboard.

More info:

Design documentation

KJS

KDE platform's JavaScript engine.

KInfoCenter

KInfoCenter originated as part of KControl standing alone from KDE 3.1. It can display data about your system such as energy usage, hardware info and many more.

More Info:

KInfoCenter
Wikipedia - KInfoCenter

KIO

KDE Input/Output framework provides a single API for operating on files, whether local or on a remote server. Additionally, KIO Slaves provide support for individual protocols. Some particularly useful ones are http, ftp, sftp, smb, nfs, ssh (fish), man, tar and zip.

More info:

A tutorial on file transfers
Wikipedia - KIO
Linux.com - Master the KIO slaves

Kiosk

Kiosk is a framework for restricting user capabilities on a KDE platform system, ideal for use in locked-down environments such as Internet cafés. It has been unmaintained for quite some time now.

KPart

A KPart is an individual component of the KDE Plasma desktop and allows applications to share their services with other applications. KParts allow KMail and KOrganizer to integrate (as plugins) into the Kontact suite, or KHTML to display sites in Akregator.

Kross

Kross is a scripting framework, enabling support for multiple scripting languages. A plugin system allows for the support of further languages in the future.

KRunner

The mini-command-line that is accessed from the Classic menu, the keyboard shortcut Alt+F2, or a right-click on the desktop.

More info:

[[Special:myLanguage/Plasma/Krunner | KRunner wiki]

KWin

KWin is the window manager of KDE. This is where window decorations can be changed and themes applied.

More info:

KWin

Pager

A pager is a small program or panel applet which shows the position of windows on your desktop and usually, if you have several Virtual Desktops, gives an overview over all.

Panel

See Kicker. In KDE Plasma the name "kicker" is dropped, and the name "panel" is the norm. "Applets"; are largely replaced by Widgets

More info:

Panels

Phonon

A cross-platform multimedia API, interfacing with existing frameworks, such as gstreamer and xine engines.

More info:

Phonon
Wikipedia - Phonon (KDE)
Phonon website

Plasma

Plasma is the desktop environment from KDE. It is the part of the desktop that you can see. Plasma also acts as a glue between panels, plasmoids and Kickoff. Plasma Mobile allows Plasma to run on smartphones and uses the same underlying code base.

More info:

Wikipedia - Plasma (KDE)
Plasma website
The Plasma main page
The Plasma FAQ's

Qt

(Pronounced "cute") A framework/toolkit for writing cross-platform applications. It is used by many cross-platform applications such as Krita, GoogleEarth and many others. Qt forms the underlying library KDE software is built on.

More info:

The Qt Toolkit

Solid

Solid provides a single API for hardware management. Hardware is grouped into "domains". The initial domains relate to HAL, NetworkManager and the Bluetooth stack. Since the backends for Solid are pluggable, Solid helps application developers write less code, and have it platform independent.

More info:

Discover Solid

System Settings

The system settings are the unified place where you can change and customize many aspects of the Plasma desktop and KWin such as icon themes, desktop effects and shortcuts.

More info:

System Settings

Threadweaver

This thread programming library spreads work among multiple-core processors where available, prioritising them before queueing them for execution. ThreadWeaver provides a high-level job interface for multithreaded programming.

More info:

Why Multithreading? (Technical article)

Virtual Desktops

A popular concept of Unix based window managers is the one of virtual desktops. This means you have not only one screen where you can place your windows on but several. When you switch to a different desktop (usually with a pager) you will only see the windows which you started on your new desktop or moved to it. A window can also be made "sticky" which means it appears on all virtual desktops.

WebKit

HTML rendering engine, originating from a fork of KHTML. Adopted by Apple and developed for Safari.

More info:

The Webkit home page
Wikipedia - Webkit

Widget

Collins English Dictionary: "Any small mechanism or device the name of which is unknown or temporarily forgotten." In KDE software terms, a widget is a single component on the canvas. Other common names that are analogous are "applet" or "gadget". Superkaramba Themes, Apple's Dashboard, Google Gadgets, Yahoo Widgets, Vista Sidebar Widgets, Opera Widgets are all examples of other widget systems (some of which are supported by Plasma as well).

X Server

The X Server represents a basic layer upon which the various GUIs like the KDE Plasma desktop are built. It manages the basic mouse and keyboard input (from the local host as well as from remote hosts) and provides elementary graphic routines to draw rectangles and other primitives.

XMLGUI

A programmers' framework for designing the user interface. It is extensively used by KParts

More info:

Wikipedia - XMLGUI
Wikipedia - Qt Style Sheets