Throughout history the development of new weapons went slowly until the 20th century, which has produced an avalanche of weapons. When the first world war began in 1914, the armies of Europe included men on horseback, armed with lances.
पूरे इतिहास में नए - नए हथियार के ईजाद होने में कोई खास तेज़ी नहीं थी, मगर इस २०वीं सदी में इतने सारे नए - नए हथियार ईजाद हुए कि मानो इनकी बाढ़ लग गयी हो ।