The world saw a dramatic growth in real GDP per capita during the 19 and 20 century. This was the most significant advance in the history of the world. I believe that technological progress accounts for the largest parts of the sharp rise in real world GDP per capita over the last two centuries.
Until the 18th century, the real world GDP per capita almost remained stable. In the 19th century, the Industrial Revolution occurred in Great Britain. The inventions such as the steam engine encouraged entrepreneurs to start new business as well as stimulated demand for capital. The profits that entrepreneurs made were allocated to savings, which in turn was invested in equipment and technology research and development. In other words, the development and innovation of technology, combined with rapid capital accumulation, accelerated the world productivity growth. The Industrial Revolution spread to Western Europe and the United States. This caused the world economy to surge exponentially.
In the 20th century, the world achieved higher economic growth thorough further progressive technical innovations. At the beginning of the 20th century, the mass production method was introduced in the US and later popularized across the world. This means that the world explosively increased the supply side capacities. In addition, because of the liberalization of trade in goods and services and investment, the world economy has expanded further.
In conclusion, the real world GDP per capita has expanded rapidly in the 19th and 20th century. I believe that this is because the continuous technological progress beginning with the Industrial Revolution, with the advent of industrialization, capitalism, and globalization, has led to the sharp increase in supply side capacities.