A Frame object is a way of grouping objects together into one container (i.e. a frame). You can draw a frame on the page using the Frame tool in the tools toolbar.

The image on the left shows the bounding box of the frame. Objects can be dragged into a frame in the Page Organiser or grouped by selecting the objects and pressing Alt+G on the keyboard.

Frames are used for a variety of reasons other than simply grouping objects. Sometimes frames are used as invisible buttons, to stop mouse clicks passing through objects or simply for visual effect as on the right: