| QAbstractEventDispatcher | Manages Qt's event queue, excluding GUI-related events |
| QAbstractItemModel | The abstract interface for item model classes |
| QAbstractListModel | Abstract model that can be subclassed to create one-dimensional list models |
| QAbstractTableModel | Abstract model that can be subclassed to create table models |
| QBasicTimer | Timer events for objects |
| QBitArray | Array of bits |
| QBuffer | QIODevice interface for a QByteArray |
| QByteArray | Array of bytes |
| QByteArrayMatcher | Holds a sequence of bytes that can be quickly matched in a byte array |
| QCache | Template class that provides a cache |
| QChar | 16-bit Unicode character |
| QChildEvent | Event parameters for child object events |
| QCoreApplication | Event loop for console Qt applications |
| QCustomEvent | Support for custom events |
| QDataStream | Serialization of binary data to a QIODevice |
| QDate | Date functions |
| QDateTime | Date and time functions |
| QDir | Access to directory structures and their contents |
| QEvent | The base class of all event classes. Event objects contain event parameters |
| QEventLoop | Means of entering and leaving an event loop |
| QFile | Interface for reading from and writing to files |
| QFileInfo | System-independent file information |
| QFlag | Helper data type for QFlags |
| QFlags | Type-safe way of storing OR-combinations of enum values |
| QGenericArgument | Internal helper class for marshalling arguments |
| QGenericReturnArgument | Internal helper class for marshalling arguments |
| QHash | Template class that provides a hash-table-based dictionary |
| QHashIterator | Java-style const iterator for QHash and QMultiHash |
| QIODevice | The base interface class of all I/O devices in Qt |
| QLatin1Char | 8-bit ASCII/Latin-1 character |
| QLatin1String | Thin wrapper around an ASCII/Latin-1 encoded string literal |
| QLibrary | Loads shared libraries at runtime |
| QLibraryInfo | Information about the Qt library |
| QLine | Two-dimensional vector that uses integer point accuracy for coordinates |
| QLineF | Two-dimensional vector that uses floating point accuracy for coordinates |
| QLinkedList | Template class that provides linked lists |
| QLinkedListIterator | Java-style const iterator for QLinkedList |
| QList | Template class that provides lists |
| QListIterator | Java-style const iterator for QList and QQueue |
| QLocale | Converts between numbers and their string representations in various languages |
| QMap | Template class that provides a skip-list-based dictionary |
| QMapIterator | Java-style const iterator for QMap and QMultiMap |
| QMetaClassInfo | Additional information about a class |
| QMetaEnum | Meta-data about an enumerator |
| QMetaMethod | Meta-data about a member function |
| QMetaObject | Meta-information about Qt objects |
| QMetaProperty | Meta-data about a property |
| QMetaType | Manages named types in the meta object system |
| QMimeData | Container for data that records information about its MIME type |
| QModelIndex | Used to locate data in a data model |
| QMultiHash | Convenience QHash subclass that provides multi-valued hashes |
| QMultiMap | Convenience QMap subclass that provides multi-valued maps |
| QMutableHashIterator | Java-style non-const iterator for QHash and QMultiHash |
| QMutableLinkedListIterator | Java-style non-const iterator for QLinkedList |
| QMutableListIterator | Java-style non-const iterator for QList and QQueue |
| QMutableMapIterator | Java-style non-const iterator for QMap and QMultiMap |
| QMutableVectorIterator | Java-style non-const iterator for QVector and QStack |
| QMutex | Access serialization between threads |
| QMutexLocker | Convenience class that simplifies locking and unlocking mutexes |
| QObject | The base class of all Qt objects |
| QObjectCleanupHandler | Watches the lifetime of multiple QObjects |
| QPair | Template class that stores a pair of items |
| QPersistentModelIndex | Used to locate data in a data model |
| QPluginLoader | Loads a plugin at run-time |
| QPoint | Defines a point in the plane |
| QPointF | Point object that uses floating point coordinates for accuracy |
| QPointer | Template class that provides guarded pointers to QObjects |
| QProcess | Used to start external programs and to communicate with them |
| QQueue | Generic container that provides a queue |
| QReadLocker | Convenience class that simplifies locking and unlocking read-write locks for read access |
| QReadWriteLock | Read-write locking |
| QRect | Defines a rectangle in the plane that uses integer point accuracy for coordinates |
| QRectF | Defines a rectangle in the plane using floating point coordinates for accuracy |
| QRegExp | Pattern matching using regular expressions |
| QSemaphore | General counting semaphore |
| QSet | Template class that provides a hash-table-based set |
| QSetIterator | Java-style const iterator for QSet |
| QSettings | Persistent platform-independent application settings |
| QSharedData | Base class for shared data objects |
| QSharedDataPointer | Pointer to a shared data object |
| QSignalMapper | Bundles signals from identifiable senders |
| QSize | Defines the size of a two-dimensional object |
| QSizeF | Defines the size of a two-dimensional object using floating point values for accuracy |
| QSocketNotifier | Support for monitoring activity on a file descriptor |
| QStack | Template class that provides a stack |
| QString | Unicode character string |
| QStringList | List of strings |
| QStringMatcher | Holds a sequence of characters that can be quickly matched in a Unicode string |
| QSysInfo | Information about the system |
| QTemporaryFile | I/O device that operates on temporary files |
| QTextCodec | Conversions between text encodings |
| QTextCodecPlugin | Abstract base for custom QTextCodec plugins |
| QTextDecoder | State-based decoder |
| QTextEncoder | State-based encoder |
| QTextIStream | Convenience class for input streams |
| QTextOStream | Convenience class for output streams |
| QTextStream | Convenient interface for reading and writing text |
| QThread | Platform-independent threads |
| QThreadStorage | Per-thread data storage |
| QTime | Clock time functions |
| QTimer | Repetitive and single-shot timers |
| QTimerEvent | Parameters that describe a timer event |
| QTranslator | Internationalization support for text output |
| QUrl | Convenient interface for working with URLs |
| QUuid | Stores a Universally Unique Identifier (UUID) |
| QVarLengthArray | Low-level variable-length array |
| QVariant | Acts like a union for the most common Qt data types |
| QVector | Template class that provides a dynamic array |
| QVectorIterator | Java-style const iterator for QVector and QStack |
| QWaitCondition | Condition variable for synchronizing threads |
| QWriteLocker | Convenience class that simplifies locking and unlocking read-write locks for write access |
