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Facets: Additional search filters, which appear on the left side of search results UI in Hyku (and Blacklight apps in general). These are typically indexed based on metadata and while Hyku has a default set, additional ones can be created by a developer.
FileSet: A set of files that represent the same file. For example, a book might include tiff, pdf, and text files representing the same page, or tiff, svg, and png files representing the same image.
Gem: In this context, a gem is an add-on to Hyku Core to make other features possible. A “gem” is a term specific to the Ruby coding language and Rails framework, which Samvera applications utilize, and is an optional code library that can be implemented into code.
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