These are the five elements of the dell boomi platform.
Integrate: Connect applications across your environment regardless of where they reside. It could be on-perm or cloud.
Hub: Capability to master customer data across all systems enabling a single master data repository.
Exchange: EDI and trading partner management.
Mediate: Manage your APIs with mediation,throttling,analytics etc.
Boomi Flow, Drag and Drop supported workflow and web application development platform
References – Dell Boomi