Cytoscape - Cytoscape Official Web Site
UCINET - UCINET for Windows is a software package for the analysis of social network data.
Gephi - Gephi is an open-source software for visualizing and analyzing large networks graphs.
NodeXL - Home
VOSviewer - VOSviewer is a software tool for constructing and visualizing bibliometric networks.
Pajek - Pajek is a lightweight solution developed from scratch by an extraordinary team of developers for the purpose of Large Network Analysis.