After the slow intellectual growth of the Middle Ages, things picked up. By the dawn of the 15th century, technology was on a roll. The next couple of centuries produced some extremely important inventions. Books, as we know them today, were born when moveable type was invented in what is now Germany. The feudal system died when gunpowder made its way to Europe from China and made armored knights obsolete. Many things still in common use today—oil paint, telescopes, screwdrivers, and pencils, to name a few—made their first appearances.

What name do we give to the 15th and 16th centuries and this time of great invention? It’s the Age of Early Modern Science, when science as we think of it today began.

The Age of Early Modern Science started slowly. Religious leaders of the time persecuted scientists who spread ideas that contradicted their strict interpretation of the holy books. For example, Catholic church leaders forbade people (those few who could read, anyway) from reading any book that was placed on the dreaded Index Librorum Prohibitorum (the Index of Prohibited Books). Nicholas Copernicus, Galileo Galilei, and Johannes Keppler (who wrote that the earth revolved around the sun instead of the other way around) were just a few of the great scientists whose books were placed on the Index.

Eventually, the tide of exploration and the new knowledge that it brought could not be stemmed and scientific thinkers were freer (although not until much later would scientists be altogether free) to express their ideas without the fear of being deemed heretics.

These thinkers, led by Galileo Galilei, Nicholas Copernicus, and Isaac Newton, accumulated scientific knowledge far more rapidly than the scientific community ever had previously. Advances in physics, chemistry, and mathematics ushered in a whole new way for people of the time (at least educated people) to separate science from superstition and understand the world as it really is.

This section introduces three makers that you may not have ever heard of—two men and one woman. The things they invented—the tools of modern fishing, a way to make accurate maps, and a method for creating a vacuum—didn’t make them particularly rich or famous. But those inventions were still very important and we use them in many ways in our modern daily lives.