In many GIS software, what is called a project includes all the layers of information, parameters of display, the results of analyses, selections, which the user chooses to save at the end of a session. In a project file, only links to data are stored, as well as the symbology (the display), the labels, the graphics … A change in a project therefore causes no change in the original data. It is imperative not to move or modify the original files (source files) in order to open the project later.
See also: GIS Software, Data organization
[French: Fichiers (Projet)]