I think the biggest advancement in human history was the industrial revolution.
The industrial revolution caused us to transition from an agricultural society to an industrial society.
The industrial revolution helped lead to capitalism (which is still the dominant team economic system in the world) and helped create the modern job.
The industrial revolution also lead to immense scientific and cultural advancement. Before the industrial revolution, most people were farmers and were unable to move up in society. After the industrial revolution, you could move up in society by starting a business or getting an education.
The industrial revolution helped create the modern world, and was one of the most important events in all of human history.