The CDD is a resource for the annotation of functional units in proteins. Its collection of domain models includes a set curated by NCBI, which utilizes 3D structure to provide insights into sequence/structure/function relationships.
Learn more about Conserved Domains and Protein Classification.
Structure is a molecular modeling database that contains macromolecular 3D structures derived from the Protein Data Bank, as well as tools for their visualization and comparative analysis.
Understand how the different NCBI resources are integrated to connect disparate data.
It's the real power of these tools.