QtCore

Core non-GUI classes used by other modules

QtGui

Graphical user interface components

QtMultimedia

Classes for low-level multimedia programming

QtNetwork

Classes for network programming

QtOpenGL

OpenGL support classes

QtScript

Classes for evaluating Qt Scripts

QtSql

Classes for database integration using SQL

QtSvg

Classes for displaying the contents of SVG files

QtWebKit

Classes for rendering and editing HTML

QtXml

Classes for handling XML

QtAssistant

Support for online help

QtDesigner

Classes for extending Qt Designer

QLabel

Used to display text or image

QLineEdit

Allows the user to enter one line of text

QTextEdit

Allows the user to enter multi-line text

QPushButton

A command button to invoke action

QRadioButton

Enables to choose one from multiple options

QCheckBox

Enables choice of more than one options

QSpinBox

Enables to increase/decrease an integer value

QScrollBar

Enables to access contents of a widget beyond display aperture

QSlider

Enables to change the bound value linearly.

QComboBox

Provides a dropdown list of items to select from

QMenuBar

Horizontal bar holding QMenu objects

QStatusBar

Usually at bottom of QMainWindow, provides status information.

QToolBar

Usually at top of QMainWindow or floating. Contains action buttons

QListView

Provides a selectable list of items in ListMode or IconMode

QPixmap

Off-screen image representation for display on QLabel or QPushButton object

QDialog

Modal or modeless window which can return information to parent window