For institutions managing a shared pool of resources across multiple sites. See two Omeka S examples: Constructing Gender: The Origins of Michigan’s Union and League and Yōkai Senjafuda.
Omeka S is not a replacement for Omeka Classic.
Creating an Omeka S site requires more planning than an Omeka Classic site because of additional functionality. For example, Omeka S was designed specifically with the principles of linked open data (LOD), which "enables cultural heritage institutions to publish and share their data in a way that seamlessly offers possibilities for data re-use, data enrichment and annotation increasing the visibility of collections and data for much wider audiences" (Europeana Foundation).
Every Omeka S Resource (item, item set, media) has a Uniform Resource Identifier (URI), and the core software includes Resource Description Framework (RDF) vocabularies, which maximizes its data interoperability with other data publishers. Omeka S offers users the ability to use the URIs for other Omeka S Resources as descriptive values within metadata fields, in essence linking one Omeka S Resource to another (Omeka Project).
In 2008 Omeka was introduced by the Roy Rosenzweig Center for History and New Media at George Mason University in Virginia, USA.
Omeka Classic sites are made up of three building blocks: items, collections, and exhibits. It is relatively easy to create a simple digital exhibition online, based on Dublin Core as the metadata scheme.
For further information, visit Omeka Frequently Asked Questions, which indicates differences between Omeka S and Omeka Classic.