- Qt 5.5
- All Modules
- Qt 5.5.1 Reference Documentation

# All Modules

## Qt Essentials

Qt essentials define the foundation of Qt on all platforms. They are available on all supported development platforms and on the tested target platforms. They will remain source and binary compatible during Qt 5.

Essential modules are general and useful for a majority of Qt applications. A module that is used for a special purpose is considered an add-on module even if it is available on all supported platforms.

The following table lists the Qt essentials:

Module | Description
--- | ---
Qt Core | Core non-graphical classes used by other modules.
Qt GUI | Base classes for graphical user interface (GUI) components. Includes OpenGL.
Qt Multimedia | Classes for audio, video, radio and camera functionality.
Qt Multimedia Widgets | Widget-based classes for implementing multimedia functionality.
Qt Network | Classes to make network programming easier and more portable.
Qt QML | Classes for QML and JavaScript languages.
Qt Quick | A declarative framework for building highly dynamic applications with custom user interfaces.
Qt Quick Controls | Reusable Qt Quick based UI controls to create classic desktop-style user interfaces.
Qt Quick Dialogs | Types for creating and interacting with system dialogs from a Qt Quick application.
Qt Quick Layouts | Layouts are items that are used to arrange Qt Quick 2 based items in the user interface.
Qt SQL | Classes for database integration using SQL.
Qt Test | Classes for unit testing Qt applications and libraries.
Qt WebKit (Deprecated) | Classes for a WebKit2 based implementation and a QML API. Deprecated in favor of Qt WebEngine.
Qt WebKit Widgets (Deprecated) | WebKit1 and QWidget-based classes from Qt 4.
Qt Widgets | Classes to extend Qt GUI with C++ widgets.

If you use qmake to build your projects, the Qt Core and Qt GUI modules are included by default. To link only against Qt Core, add the following line to your `.pro` file:

    QT -= gui

On Windows, if you do not use qmake or other build tools such as CMake, you also need to link against the `qtmain` library.

## Qt Add-Ons

Qt Add-On modules bring additional value for specific purposes. These modules may only be available on some development platform. Many add-on modules are either feature-complete and exist for backwards compatibility, or are only applicable to certain platforms. Each add-on module specifies its compatibility promise separately.

The Qt installers include the option of downloading the add-ons. For more information, visit the Getting Started with Qt page.

The following table lists the Qt add-ons:

Module | Development Platforms | Target Platforms | Description
--- | --- | --- | ---
Active Qt | Windows |  | Classes for applications which use ActiveX and COM
Enginio | All | All | A Backend-as-a-Service solution to ease the backend development for connected and data-driven applications.
Qt Android Extras | All | Android | Provides platform-specific APIs for Android.
Qt Bluetooth | All | Android, iOS, Linux and OS X | Provides access to Bluetooth hardware.
Qt Canvas 3D | All |  | Enables OpenGL-like 3D drawing calls from Qt Quick applications using JavaScript.
Qt Concurrent |  |  | Classes for writing multi-threaded programs without using low-level threading primitives.
Qt D-Bus | All |  | Classes for inter-process communication over the D-Bus protocol.
Qt Graphical Effects | All |  | Graphical effects for use with Qt Quick 2.
Qt Image Formats | All |  | Plugins for additional image formats: TIFF, MNG, TGA, WBMP.
Qt Mac Extras | All | OS X | Provides platform-specific APIs for OS X.
Qt NFC | All | Linux | Provides access to Near-Field communication (NFC) hardware.
Qt OpenGL |  |  | OpenGL support classes. Note: Provided to ease porting from Qt 4.x. Please use the QOpenGL classes in Qt GUI for new code
Qt Platform Headers |  |  | Provides classes that encapsulate platform-specific information, tied to a given runtime configuration of a platform plugin.
Qt Positioning | All |  | Provides access to position, satellite and area monitoring classes.
Qt Print Support | All |  | Classes to make printing easier and more portable.
Qt Declarative (Deprecated) | All |  | Qt Declarative is provided for Qt 4 compatibility. The documentation is available through the Qt 4.8 Qt Quick documentation.
Qt Quick Extras | All |  | Provides a specialized set of controls that can be used to build interfaces in Qt Quick.
Qt Quick Widgets | All |  | Provides a C++ widget class for displaying a Qt Quick user interface.
Qt Script (Deprecated) | All |  | Classes for making Qt applications scriptable. Provided for Qt 4.x compatibility. Please use the QJS* classes in the Qt QML module for new code.
Qt Script Tools | All |  | Additional components for applications that use Qt Script.
Qt Sensors | All | Android, Qt for iOS, WinRT and Mer. | Provides access to sensor hardware and motion gesture recognition.
Qt Serial Port | All | Windows, Linux, and OS X. | Provides access to hardware and virtual serial ports.
Qt SVG | All |  | Classes for displaying the contents of SVG files. Supports a subset of the SVG 1.2 Tiny standard.
Qt WebChannel | All | All | Provides access to QObject or QML objects from HTML clients for seamless integration of Qt applications with HTML/JavaScript clients.
Qt WebEngine | All | Windows, Linux, and OS X. | Provides a QML API to run web applications using the Chromium browser project.
Qt WebEngine Widgets | All | Windows, Linux, and OS X. | Provides a C++ API to run web applications using the Chromium browser project.
Qt WebSockets | All | All | Provides WebSocket communication compliant with RFC 6455.
Qt Windows Extras | All | Windows | Provides platform-specific APIs for Windows.
Qt X11 Extras | All | Linux/X11 | Provides platform-specific APIs for X11.
Qt XML |  |  | C++ implementations of SAX and DOM. Note: Deprecated, please use QXmlStreamReader and QXmlStreamWriter for new functionality.
Qt XML Patterns |  |  | Support for XPath, XQuery, XSLT and XML schema validation.

## Value-Add Modules

In addition to the modules released as part of Qt 5, the following modules and tooling build on top of the Qt libraries to provide additional value. They have their own release schedule, and are available under different Qt licenses. See the Downloads page for more information.

Feature | Description
--- | ---
Qt for Device Creation | Tools for fast, easy, and fully-integrated embedded device application development. Includes most other Value-Add features.
Qt Charts | UI Components for displaying visually pleasing charts, driven by static or dynamic data models.
Qt Quick Compiler | Enables compiling .qml source files into application binaries, improving load times and security for code assets.
Qt Data Visualization | UI Components for creating stunning 3D data visualizations.
Qt Purchasing | Enables in-app purchase of products in Qt applications on mobile platforms.
Qt Virtual Keyboard | A framework for implementing different input methods as well as a QML virtual keyboard. Supports localized keyboard layouts and custom visual themes.
Qt Quick 2D Renderer | Enables the use of Qt Quick UI on devices without OpenGL capability.

## Technology Preview Modules

The following modules are still in development but are available as technology previews.

Module | Description
--- | ---
Qt Location | Displays map, navigation, and place content in a QML application.
Qt WebView | Displays web content in a QML application by using APIs native to the platform, without the need to include a full web browser stack.
Qt3D | Functionality for near-realtime simulation systems with support for 2D and 3D rendering.

## Qt Tools

Qt Tools run on all the supported development platforms and facilitate the development and design of applications.

The following table lists the Qt tools:

Tool | Description
--- | ---
Qt Designer | Classes for extending Qt Designer.
Qt Help | Classes for integrating online documentation into applications, similar to Qt Assistant.
Qt UI Tools | Classes to handle the forms created in Qt Designer.

## Where to Go from Here

We invite you to explore the rest of Qt. We prepared overviews which help you decide which APIs to use and our examples demonstrate how to use our API.

- Qt Overviews - list of topics about application development
- Examples and Tutorials - code samples and tutorials
- Qt Reference Pages - a listing of C++ and QML APIs