Gerardus Mercator, a Flemish cartographer, is widely regarded as the father of modern cartography. He is best known for his Mercator projection, which is still widely used today for navigation and mapping.

Anaximander, an ancient Greek philosopher and cartographer, is believed to have created the first world map around 540 BC. His map was based on the idea that the Earth was a flat disk surrounded by the Oceanus, a vast river.

The Mercator projection is a cylindrical map projection that preserves angles and directions, making it useful for navigation. It is commonly used in world maps and nautical charts.

Ferdinand Magellan, a Portuguese explorer, led the first expedition to circumnavigate the globe. He set sail in 1519 with five ships and completed the journey in 1522, although he himself did not survive the entire voyage.

Juan de la Cosa, a Spanish cartographer and explorer, is known for his detailed maps of the Americas. His map of 1500 is considered one of the earliest and most accurate maps of the New World.

Abraham Ortelius, a Flemish cartographer, is credited with creating the first modern atlas, titled "Theatrum Orbis Terrarum". Published in 1570, it contained maps of the world, Europe, Asia, Africa, and America.

Eratosthenes, a Greek mathematician and geographer, is credited with developing the concept of latitude and longitude. He also made significant contributions to cartography, including calculating the circumference of the Earth.

Piri Reis, an Ottoman cartographer and admiral, is known for creating the portolan chart, a type of nautical chart that was widely used by sailors in the Mediterranean Sea.

Martin Waldseemüller, a German cartographer, is known for creating the map of the world titled "Universalis Cosmographia". This map is significant as it is the first to use the name "America" for the New World.

Lewis and Clark, the famous American explorers, are credited with creating the first accurate map of the United States. Their expedition from 1804 to 1806 provided valuable geographical information about the western territories.

John Snow, an English physician and cartographer, is known for his contributions to thematic cartography. His famous cholera map of London in 1854 helped identify the source of the cholera outbreak and led to improved sanitation measures.

Jacques Bertin, a French cartographer, is considered the father of modern thematic cartography. His work on visual variables and the semiology of graphics revolutionized the way thematic maps are designed and communicated.

Charles Minard, a French engineer and cartographer, is known for his innovative use of graphics and diagrams in data visualization. His famous "Flow Map of Napoleon's Russian Campaign" is considered a masterpiece of cartographic design.

Florence Nightingale, a British nurse and statistician, is credited with developing the Nightingale rose diagram. This diagram is a type of polar area diagram used to visualize statistical data, particularly in the field of healthcare.

John Snow, in addition to his work on thematic cartography, is also known for his contributions to the development of choropleth maps. Choropleth maps use different colors or shades to represent the distribution of a quantitative variable across a geographic area.