  Complex networks have attracted a great deal of research interest in the last
two decades since Watts & Strogatz, Barab\'asi & Albert and Girvan & Newman
published their highly-cited seminal papers on small-world networks, on
scale-free networks and on the community structure of complex networks,
respectively. These fundamental papers initiated a new era of research
establishing an interdisciplinary field called network science. Due to the
multidisciplinary nature of the field, a diverse but not divided network
science community has emerged in the past 20 years. This paper honors the
contributions of network science by exploring the evolution of this community
as seen through the growing co-authorship network of network scientists (here
the notion refers to a scholar with at least one paper citing at least one of
the three aforementioned milestone papers). After investigating various
characteristics of 29,528 network science papers, we construct the
co-authorship network of 52,406 network scientists and we analyze its topology
and dynamics. We shed light on the collaboration patterns of the last 20 years
of network science by investigating numerous structural properties of the
co-authorship network and by using enhanced data visualization techniques. We
also identify the most central authors, the largest communities, investigate
the spatiotemporal changes, and compare the properties of the network to
scientometric indicators.
