Anarchist Émile Henry hurls a bomb into the Cafe Terminus in Paris, killing one person and wounding 20.

mile Henry (26 September 1872 21 May 1894) was a French anarchist, who on 12 February 1894 detonated a bomb at the Caf Terminus in the Parisian Gare Saint-Lazare killing one person and wounding twenty.

Though his activity in the anarchist movement was limited, he garnered much attention as a result of his crimes and of his age. He was also seen as one of the first people of a growing group of revolutionaries (largely anarchist) who subscribed to the doctrine of the "propaganda of the deed", which would later take the life of many governmental figures.

Anarchism is a political philosophy and movement that is sceptical of authority and rejects all involuntary, coercive forms of hierarchy. Anarchism calls for the abolition of the state, which it holds to be unnecessary, undesirable, and harmful. As a historically left-wing movement, placed on the farthest left of the political spectrum, it is usually described alongside communalism and libertarian Marxism as the libertarian wing (libertarian socialism) of the socialist movement, and has a strong historical association with anti-capitalism and socialism.

Humans lived in societies without formal hierarchies long before the establishment of formal states, realms, or empires. With the rise of organised hierarchical bodies, scepticism toward authority also rose. Although traces of anarchist thought are found throughout history, modern anarchism emerged from the Enlightenment. During the latter half of the 19th and the first decades of the 20th century, the anarchist movement flourished in most parts of the world and had a significant role in workers' struggles for emancipation. Various anarchist schools of thought formed during this period. Anarchists have taken part in several revolutions, most notably in the Paris Commune, the Russian Civil War and the Spanish Civil War, whose end marked the end of the classical era of anarchism. In the last decades of the 20th and into the 21st century, the anarchist movement has been resurgent once more.

Anarchism employs a diversity of tactics in order to meet its ideal ends which can be broadly separated into revolutionary and evolutionary tactics; there is significant overlap between the two, which are merely descriptive. Revolutionary tactics aim to bring down authority and state, having taken a violent turn in the past, while evolutionary tactics aim to prefigure what an anarchist society would be like. Anarchist thought, criticism, and praxis have played a part in diverse areas of human society. Criticism of anarchism include claims that it is internally inconsistent, violent, or utopian.