to the Semantic Web and Social Networks.- The Semantic Web.- Social Network Analysis.- Web data and semantics in social network applications.- Electronic sources for network analysis.- Knowledge Representation on the Semantic Web.- Modelling and aggregating social network data.- Developing social-semantic applications.- Case studies.- Evaluation of web-based social network extraction.- Semantic-based Social Network Analysis in the sciences.- Ontologies are us: emergent semantics in folksonomy systems.- Conclusions.- The perfect storm.