The processing toolbox serves as a one-stop-shopping GUI for accessing algorithms from both native QGIS tools and many third-party providers. Historically, the algorithms from other geospatial packages were only accessible within the native software environment or through a command-line environment. Algorithms from the following providers are accessible using the toolbox:

We will not make use of all the algorithm providers or explore all the available algorithms in this chapter; however, the last two entries in the list offer additional options for creating reusable graphical models and running Python scripts, which are covered in Chapter 8, Automating Workflows with the Graphical Modeler, and Chapter 9, Creating QGIS Plugins with PyQGIS and Problem Solving, respectively.