This research presents a data set of the terrorist attacks that took place in Western countries between 11th
September 2001 and 31st December 2016. The study begins by addressing both the conceptual problem of
the definition of terrorism and its political significance, and the historical origins of Islamic or jihadist terrorism. The data set used here is based on the University of Maryland’s Global Terrorism Database, which
has been integrated and extended using journalistic sources, scientific journals, and governmental and institutional websites. The general and specific traits of the terrorist phenomenon are investigated through
multidimensional analysis of the data (AMD) and the analysis of their main components (ACP). The analysis
throws into relief both the variety of the terrorist attacks and of the terrorist organizations involved, and
in particular, how the modus operandi of the cells linked to Al-Qaida differ compared to those attached to
other subjects or groups.
