Fiori is a collection of Business Apps from SAP that can run on mobile, tablet and desktop. These apps are developed using Design Thinking methodology and follow specific design guidelines.
However, SAP Fiori is an umbrella term used for the User Experience(UX) strategy SAP has come up with. It has to do with the front end / UI development.
This strategy has various technologies under it like SAPUI5, Fiori Launchpad, Theme Designer etc.
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