The #QScrollBar widget is a scroll bar that enables the user to access parts of a document that is larger than the widget used to display it.
https://doc.qt.io/qtforpython-5/PySide2/QtWidgets/QScrollBar.html
The #QScrollArea widget is used to display the contents of a child widget within a frame. If the widget exceeds the size of the frame, the view can provide scroll bars so that the entire area of the child widget can be viewed.
https://doc.qt.io/qtforpython-5/PySide2/QtWidgets/QScrollArea.html
