Greenstone allows you to download files from the internet using a variety of protocols:

• Web: downloads web pages and files via HTTP and FTP.
• MediaWiki: downloads web pages and files via HTTP from a MediaWiki website.
• OAI: downloads metadata records (and optionally documents) from an OAI-PMH (Open Archives Initiative) server.
• Z39.50: downloads MARC records that match a particular search criterion from a Z39.50 server.
• SRW/SRU: downloads MARCXML records that match a particular search criterion from a Search/Retrieve via URL (SRU) server.

This can be done from either the Download panel of the GLI, or directly from the command line.

There are several tutorials on downloading files using various protocols: