Glue language

Python is often called a "glue" language. This term describes the use of Python code to control other software programs by sending inputs to their Application Programming Interface (API) and collecting outputs, which are then sent to another program to repeat the process. A GIS example would be to use Python's urllib2 to download zipped shapefiles from a website, unzipping the files, processing the files using ArcToolbox, and compiling the results into an Excel spreadsheet. All of this is accomplished using freely available modules that are either included in Python's built-in library, or added on when ArcGIS is installed.