A globe is a very useful thing but it has certain limitations. You can use a globe when you need to have an overall view of the whole earth. A globe does not show details of a country or a state. When you need to study details about a small place then you need to use a map.
Map: A map is a representation drawing of earth’s surface or a part of it on a flat surface. Maps are drawn according to scale. It is difficult to represent a spherical surface on a flat surface. Specially trained people draw maps and they are called cartographer.
There can be different types of maps. Some of them are as follows:
Physical Map: A physical map shows physical features of the earth. Mountains, plains, plateau, desert, rivers, oceans, etc. come under the physical features. A physical map is also called relief map.
Political Map: A political map shows boundaries of towns, cities, states, countries, etc.
Thematic Map: Thematic maps show specific information. For example; a road map shows the road network of an area. Similarly, a rail map shows the rail network of an area. A thematic map can show various industries, crop production, population density, etc.
There are three components of map, viz. distance, direction and symbol.
Maps are two-dimensional drawings. It reduces the entire world or a part of the world on a small sheet of paper. While making a map, cartographers pay attention to properly represent the distance between two places. This helps us in finding the actual distance between two places.
For this, a suitable scale is used for the map. Let us take the example of distance between Delhi and Patna; which is about 1000 km. On a map, this may be shown by a ten centimeter long line. In that case, one centimeter on the map represents 100 km. So, the scale of the map is 1 cm = 100 km.
Small Scale Map: When a large area is shown on a small map, such a map is called a small scale map. Example; map of a country or state.
Large Scale Map: When a small area such as a village is shown on a map, such a map is called a large scale map. A map of a neighbourhood is another example of large scale map. A large scale map gives more details compared to a small scale map.
A map also contains information about directions. On most of the maps, you will usually see an upward arrow and the letter ‘N’. This shows the north direction. Once we know the north, we can easily find the other directions. North, South, East and West are the four major directions. These are called Cardinal Directions. Some maps also show the intermediate directions, viz. north-east, south-east, south-west and north-west.
Compass: Compass is very useful for finding directions at a place. This is a small circular box with a magnetic needle inside. The needle of the compass always points in the north-south direction. Compass has been used by travelers and sailors since ages.
Cartographers also need to show various details; like important structures, landmarks, etc. on a map. These things are shown by some standard symbols on the map. You can understand that it is not possible to draw pictures of hospital or temple or railway line or a monument on a map because of the lack of space. Hence some conventional symbols have been made on the basis of an international agreement.
While using colours to show different themes and items on a map; certain conventions are followed. Mountains are usually shown in brown colour, plains in green, water body in blue and plateau is shown in yellow.
A drawing based on memory is called a sketch. A sketch is not made to scale. A sketch map is useful when you need to show directions to your house to your friend.
Drawing of a small area on a large scale is called a plan. Architects usually make plans to show the layout of a house.
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