# Implicitly Shared Classes

These classes are normally-heavy classes which in Qt have been optimized by the use of reference counter and common data so they can be passed around.

The only important effect is that the classes listed here can be passed around as arguments, even though they may seem heavyweight.

Classes:

- QBitArray (Array of bits)
- QBitmap (Monochrome (1 bit depth) pixmaps)
- QBrush (Defines the fill pattern of shapes drawn by a QPainter)
- QByteArray (Array of bytes)
- QCursor (Mouse cursor with an arbitrary shape)
- QPalette (Color groups for each widget state)
- QPen (Defines how a QPainter should draw lines and outlines of shapes)
- QPixmap (Off-screen pixel-based paint device)
- QString (Abstraction of the classic C zero-terminated char array (char*))