Moore's Law has driven 50 years of computing progress

In 1965, Gordon Moore — co-founder of Intel — observed that the number of transistors on a microchip had doubled roughly every two years, while costs halved. He predicted this trend would continue. It did, for five decades. A modern smartphone contains more than 15 billion transistors; the Intel 4004 processor in 1971 had 2,300. Physicists now believe Moore's Law is approaching its physical limits as transistors reach the size of individual atoms, prompting a race toward quantum computing and 3D chip stacking.

Source: Moore, Cramming More Components onto Integrated Circuits, Electronics (1965)