There are a number of tasks you typically carry out on your project, such as loading it, creating a saved state, debugging it, etc. Good practice on large projects is to define small files that hold the commands to execute such a task, name this file after the task and give it a file extension that makes starting easy (see section 18.104.22.168). The task load is generally central to these tasks. Here is a tentative list:
Use this file to set up the environment (Prolog flags and file search paths) and load the sources. Quite commonly this file also provides convenient predicates to parse command line options and start the application.
Use this file to start the application. Normally it loads
load.plin silent-mode, and calls one of the starting predicates from
Use this file to create a saved state of the application by loading
load.pland calling qsave_program/2 to generate a saved state with the proper options.
Loads the program for debugging. In addition to loading
load.plthis file defines rules for portray/1 to modify printing rules for complex terms and customisation rules for the debugger and editing environment. It may start some of these tools.