What Map Is
A map is a graphic representation or scale model of spatial concepts. It is a means for conveying geographic information. Maps are a universal medium for communication, easily understood and appreciated by most people, regardless of language or culture. Incorporated in a map is the understanding that it is a "snapshot" of an idea, a single picture, a selection of concepts from a constantly changing database of geographic information.
Old maps provide much information about what was known in times past, as well as the philosophy and cultural basis of the map, which were often much different from modern cartography. Maps are one means by which scientists distribute their ideas and pass them on to future generations.
Are maps realistic representations of the actual world? No--never! Field measurements are subject to errors of accuracy and precision. Aerial photographs and satellite images portray only certain portions of the light spectrum, as filtered through the atmosphere and detection instruments. No map can depict all physical, biological, and cultural features for even the smallest area. A map can display only a few selected features, which are portrayed usually in highly symbolic styles according to some kind of classification scheme. In these ways, all maps are estimations, generalizations, and interpretations of true geographic conditions.
All maps are made according to certain basic assumptions, for example sea-level datum, which are not always true or verifiable. Finally any map is the product of human endeavor, and as such may be subject to unwitting errors, misrepresentation, bias, or outright fraud. In spite of these limitations, maps have proven to be remarkably adaptable and useful through several millennia of human civilization. Maps of all kinds are fundamentally important for modern society.
The Art of Cartography
Cartography is the art and science of map making, practiced by cartographers. Humans have been drawing maps for thousands of years, as part of an effort to understand their environment. The quest for an accurate map drove explorers to adventure to far-flung areas well into the 1700s, and cartographers in the modern day find frequent employment still, thanks to constant political and geological changes around the world. To train in cartography, a student should be prepared to take years of courses in multiple disciplines.
The term comes from two Greek words, chartis, meaning map, and graphos, meaning to draw or write. In historic times, an individual cartographer hand drew a map in entirety, often with limited information. Modern practitioners of cartography have the advantage of computers and other equipment to assist them, making their maps more precise. The science of cartography has also evolved, as many maps have become multimedia data explosions, chock full of information for the reader.
Basic cartography covers two data components. The first is location data, indicating where the area being depicted is located. In ancient maps, location data often showed where something was in relation to something else, but modern maps usually use geographical coordinates such as latitude and longitude to orient their features. The second type of data is attributional data, showing bodies of water, mountains, valleys, hills, and other geographical features of interest and of note.
A map of the world reflects an immense mathematical and aesthetic challenge, that of translating the globe to a two dimensional surface. Many cartographers have struggled with this issue over the centuries, striving to project the features of the globe accurately and effectively. Numerous approaches have been taken to solve this problem, including the Mercator Projection, a map which distorts geological features north and south of the Equator in order to fit the globe into a neat rectangle. Other maps portray the globe in sections, reducing the amount of distortion necessary.
The skills needed for cartography are immense. Cartography relies heavily on math to represent the Earth, along with science to help describe and understand geological features. Specialized maps may include things like ocean soundings, which requires a knowledge of oceanography, or unique rock formations, which implies geological study of the region. Knowledge of ongoing political events is also important, as nations divide, change names, or disappear more frequently than many people realize.
The products of cartography can be divided into two rough types of map, although they may frequently overlap. A topographical map is one which is designed to be true to the landscape that it is depicting. Topographical maps usually include elevations, major geographical features, and other information which someone who use to orient him or herself. These maps can often be used for decades, unless a major geological event such as a volcanic eruption or earthquake occurs.
A topological map, on the other hand, is used for conveying information such as highway routes, dangerous regions of a country, or population density. Topological maps can sometimes be quite complex, showing multiple important features to readers to highlight and educate, and they change frequently as the lives of the people and places depicted on them change.
History of Maps
Early Maps
The oldest known maps are preserved on Babylonian clay tablets from about 2300 B.C. Cartography was considerably advanced in ancient Greece. The concept of a spherical Earth was well known among Greek philosophers by the time of Aristotle (ca. 350 B.C.) and has been accepted by all geographers since. Greek and Roman cartography reached a culmination with Claudius Ptolemaeus (Ptolemy, about A.D. 85-165). His "world map" depicted the Old World from about 60°N to 30°S latitudes. He wrote a monumental work, Guide to Geography (Geographike hyphygesis), which remained an authorative reference on world geography until the Renaissance.
Medieval Maps
During the Medieval period, European maps were dominated by religious views. The T-O map was common. In this map format, Jerusalem was depicted at the center and east was oriented toward the map top. Viking explorations in the North Atlantic gradually were incorporated into the world view beginning in the 12th century. Meanwhile, cartography developed along more practical and realistic lines in Arabic lands, including the Mediterranean region. All maps were, of course, drawn and illuminated by hand, which made the distribution of maps extremely limited.
Renaissance Maps
The invention of printing made maps much more widely available beginning in the 15th century. Maps were at first printed using carved wooden blocks. Printing with engraved copper plates appeared in the 16th century and continued to be the standard until photographic techniques were developed. Major advances in cartography took place during the Age of Exploration in the 15th and 16th centuries. Map makers responded with navigation charts, which depicted coast lines, islands, rivers, harbors, and features of sailing interest. Compass lines and other navigation aids were included. Such maps were held in great value for economic, military, and diplomatic purposes, and so were often treated as national or commercial secrets--classified or proprietary maps.
The first whole world maps began to appear in the early 16th century, following voyages by Columbus and others to the New World. Gerardus Mercator of Flanders (Belgium) was the leading cartographer of the mid-16th century. He developed a cylindrical projection that is still widely used for navigation charts and global maps. He published a map of the world in 1569 based on this projection. Many other map projections were soon developed.
Modern Maps
Maps became increasingly accurate and factual during the 17th, 18th and 19th centuries with the application of scientific methods. Many countries undertook national mapping programs. Nonetheless, much of the world was poorly known until the widespread use of aerial photography following World War II. Modern cartography is based on a combination of ground observations and remote sensing.
Geographic information systems (GIS) emerged in the 1970-80s period. GIS represents a major shift in the cartography paradigm. In traditional (paper) cartography, the map was both the database and the display of geographic information. For GIS, the database, analysis, and display are physically and conceptually separate aspects of handling geographic data. Geographic information systems comprise computer hardware, software, digital data, people, organizations, and institutions for collecting, storing, analyzing, and displaying georeferenced information about the Earth.
A map is a graphic representation or scale model of spatial concepts. It is a means for conveying geographic information. Maps are a universal medium for communication, easily understood and appreciated by most people, regardless of language or culture. Incorporated in a map is the understanding that it is a "snapshot" of an idea, a single picture, a selection of concepts from a constantly changing database of geographic information.
Old maps provide much information about what was known in times past, as well as the philosophy and cultural basis of the map, which were often much different from modern cartography. Maps are one means by which scientists distribute their ideas and pass them on to future generations.
Are maps realistic representations of the actual world? No--never! Field measurements are subject to errors of accuracy and precision. Aerial photographs and satellite images portray only certain portions of the light spectrum, as filtered through the atmosphere and detection instruments. No map can depict all physical, biological, and cultural features for even the smallest area. A map can display only a few selected features, which are portrayed usually in highly symbolic styles according to some kind of classification scheme. In these ways, all maps are estimations, generalizations, and interpretations of true geographic conditions.
All maps are made according to certain basic assumptions, for example sea-level datum, which are not always true or verifiable. Finally any map is the product of human endeavor, and as such may be subject to unwitting errors, misrepresentation, bias, or outright fraud. In spite of these limitations, maps have proven to be remarkably adaptable and useful through several millennia of human civilization. Maps of all kinds are fundamentally important for modern society.
The Art of Cartography
Cartography is the art and science of map making, practiced by cartographers. Humans have been drawing maps for thousands of years, as part of an effort to understand their environment. The quest for an accurate map drove explorers to adventure to far-flung areas well into the 1700s, and cartographers in the modern day find frequent employment still, thanks to constant political and geological changes around the world. To train in cartography, a student should be prepared to take years of courses in multiple disciplines.
The term comes from two Greek words, chartis, meaning map, and graphos, meaning to draw or write. In historic times, an individual cartographer hand drew a map in entirety, often with limited information. Modern practitioners of cartography have the advantage of computers and other equipment to assist them, making their maps more precise. The science of cartography has also evolved, as many maps have become multimedia data explosions, chock full of information for the reader.
Basic cartography covers two data components. The first is location data, indicating where the area being depicted is located. In ancient maps, location data often showed where something was in relation to something else, but modern maps usually use geographical coordinates such as latitude and longitude to orient their features. The second type of data is attributional data, showing bodies of water, mountains, valleys, hills, and other geographical features of interest and of note.
A map of the world reflects an immense mathematical and aesthetic challenge, that of translating the globe to a two dimensional surface. Many cartographers have struggled with this issue over the centuries, striving to project the features of the globe accurately and effectively. Numerous approaches have been taken to solve this problem, including the Mercator Projection, a map which distorts geological features north and south of the Equator in order to fit the globe into a neat rectangle. Other maps portray the globe in sections, reducing the amount of distortion necessary.
The skills needed for cartography are immense. Cartography relies heavily on math to represent the Earth, along with science to help describe and understand geological features. Specialized maps may include things like ocean soundings, which requires a knowledge of oceanography, or unique rock formations, which implies geological study of the region. Knowledge of ongoing political events is also important, as nations divide, change names, or disappear more frequently than many people realize.
The products of cartography can be divided into two rough types of map, although they may frequently overlap. A topographical map is one which is designed to be true to the landscape that it is depicting. Topographical maps usually include elevations, major geographical features, and other information which someone who use to orient him or herself. These maps can often be used for decades, unless a major geological event such as a volcanic eruption or earthquake occurs.
A topological map, on the other hand, is used for conveying information such as highway routes, dangerous regions of a country, or population density. Topological maps can sometimes be quite complex, showing multiple important features to readers to highlight and educate, and they change frequently as the lives of the people and places depicted on them change.
History of Maps
Early Maps
The oldest known maps are preserved on Babylonian clay tablets from about 2300 B.C. Cartography was considerably advanced in ancient Greece. The concept of a spherical Earth was well known among Greek philosophers by the time of Aristotle (ca. 350 B.C.) and has been accepted by all geographers since. Greek and Roman cartography reached a culmination with Claudius Ptolemaeus (Ptolemy, about A.D. 85-165). His "world map" depicted the Old World from about 60°N to 30°S latitudes. He wrote a monumental work, Guide to Geography (Geographike hyphygesis), which remained an authorative reference on world geography until the Renaissance.
Medieval Maps
During the Medieval period, European maps were dominated by religious views. The T-O map was common. In this map format, Jerusalem was depicted at the center and east was oriented toward the map top. Viking explorations in the North Atlantic gradually were incorporated into the world view beginning in the 12th century. Meanwhile, cartography developed along more practical and realistic lines in Arabic lands, including the Mediterranean region. All maps were, of course, drawn and illuminated by hand, which made the distribution of maps extremely limited.
Renaissance Maps
The invention of printing made maps much more widely available beginning in the 15th century. Maps were at first printed using carved wooden blocks. Printing with engraved copper plates appeared in the 16th century and continued to be the standard until photographic techniques were developed. Major advances in cartography took place during the Age of Exploration in the 15th and 16th centuries. Map makers responded with navigation charts, which depicted coast lines, islands, rivers, harbors, and features of sailing interest. Compass lines and other navigation aids were included. Such maps were held in great value for economic, military, and diplomatic purposes, and so were often treated as national or commercial secrets--classified or proprietary maps.
The first whole world maps began to appear in the early 16th century, following voyages by Columbus and others to the New World. Gerardus Mercator of Flanders (Belgium) was the leading cartographer of the mid-16th century. He developed a cylindrical projection that is still widely used for navigation charts and global maps. He published a map of the world in 1569 based on this projection. Many other map projections were soon developed.
Modern Maps
Maps became increasingly accurate and factual during the 17th, 18th and 19th centuries with the application of scientific methods. Many countries undertook national mapping programs. Nonetheless, much of the world was poorly known until the widespread use of aerial photography following World War II. Modern cartography is based on a combination of ground observations and remote sensing.
Geographic information systems (GIS) emerged in the 1970-80s period. GIS represents a major shift in the cartography paradigm. In traditional (paper) cartography, the map was both the database and the display of geographic information. For GIS, the database, analysis, and display are physically and conceptually separate aspects of handling geographic data. Geographic information systems comprise computer hardware, software, digital data, people, organizations, and institutions for collecting, storing, analyzing, and displaying georeferenced information about the Earth.
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