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{{man tip|Information on developing for Gramps}}
The Gramps signaling system is used to pass changes in the db, GUI, or other sources to various elements (usually , the GUI) that need to be updated when changes occur.
Signals are emitted by the source, processed by the callback system and managers and result in callbacks to the GUI (or other) elements that have done a 'connect' to the callback manager for the signal of interest.
Signals from the db can indicate the types of db changes, such as an add, update or delete of one of the primary objects. Examples of these signals are 'person-add', 'media-update', 'citation-delete', 'note-deleterebuild'. This type of signal is emitted with a list of handles of the primary objects affected as arguments.
The GUI also emits signals when some user action changes the state; on a given view the 'active-changed' signal indicates that the selected object has changed. In addition, Gtk provides a rich set of signals for their widgets that use the separate (but similar) Gtk signal system.
