SWORD provides a simple to use engine for working with many types of texts including Bibles, commentaries, lexicons, glossaries, daily devotionals, and others.
Some main classes:
SWMgr gives access to an installed library of modules (books). SWModule represents an individual module SWKey represents a location into a module (e.g. "John 3:16")
An API Primer can be found at:
http://crosswire.org/sword/develop/swordapi/apiprimer.jsp
If you're interested in working on a client which uses SWORD, please first have a look at some of the existing ones. They can always use help, and will also prove to be good examples if you decide to start a new project.
Well known frontends are:
-SWORD for Windows (http://crosswire.org/sword/software/biblecs/)
-GnomeSword (http://gnomesword.sourceforge.net/)
-BibleTime (http://www.bibletime.info/)
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