Geography is an extremely broad discipline that seeks to map and describe both the physical features of the Earth, like mountains, and its human features, such as the borders of countries or distributions of religions. The word, first used by Eratosthenes (276 – 194 BCE), literally means “writing about the Earth.” It is sometimes called “the bridge between the physical and human sciences,” but is divided into two branches that focuses on each separately: human and physical.
This discipline can be divided into about a dozen sub-categories per major branch. In physical geography, the sub-categories include biogeography, climatology, paleoclimatology, coastal, environmental, geodesy (geo-measurement), geomorphology, hydrography, glaciology, landscape ecology, oceanography, pedology (soil study), paleogeography, and quaternary science (study of the last 2.6 million years). In human geography, the sub-categories include development, cultural, economic, health, historical, population, political, religion, social, transportation, tourism, and urban geography.
Geography has been practiced at least since Classical Antiquity, around 600 BC. Anaximander of Miletus is the first true geographer, according to slightly later Greek sources. In ancient times, only Europe, the Near East, and North Africa were recognized by the West. Other global civilizations, such as the Inca, ancient China, and ancient India were similarly isolated, knowing little about the world beyond the immediate area. During the late 13th century, the famous explorer Marco Polo traveled from Europe to China, making Europeans more aware of the far East, and culturally linking the two distant places. Modern geography really began during the Age of Exploration, beginning in the 15th century, when the Americas were added to maps and many people around the world became aware of five continents. Australia was not discovered until the 17th century, and Antarctica not until 1820.
Today, modern geography is an advanced discipline. Thanks to satellite imagery, the Earth has been mapped to a resolution better than approximately 10 m, and military satellites are thought to have a resolution of 10 cm. The exact altitudes of most major mountains are known to within a few meters. Software programs such as Google Maps make precise geographical information available to anyone with an Internet connection.