The Global Positioning system (GPS) is a U.S. space-based global navigation satellite system. It provides a reliable positioning, navigation and timing services to worldwide users on a continuous basis in all weather conditions, either day or night, anywhere on or near the Earth, which has an unobstructed view of four or more GPS satellites.

A sketch is a drawing, mainly based on memory and spot observation and not to scale. Such a rough drawing is drawn without scale and is called a sketch map.

When large areas like continents or countries are to be shown on paper, we use a small scale. For example, if 5 cm. on a map shows 500 km. on the ground, it is called a Small-Scale map.

Maps which focus on specific information, such as road maps, rainfall maps, showing distribution of forests, industries, etc. are known as Thematic Maps. Suitable titles may be given on the basis of information provided by these maps.

A globe is of little use when we want to study only a part of the earth like districts, country, states, towns and villages. While maps are helpful to study small parts or areas with specific informations.

The titles given to thematic maps are based on the information given in the map. They contain specific information like-networks of roads, distribution of forests, distribution of industries etc.

Compass is an instrument that is used to find out main directions. The magnetic needle of the compass always points towards North-South direction and after knowing North, other directions can be identified easily.

The four cardinal directions are North, South, East and West.

We need to understand maps because of the following reason :
(i) To find our way around a city.
(ii) To find the location of specific places in a new city.
(iii) To find the shortest route to a specific spot.
(iv) To find out locations of petrol pumps, police station and rest houses on highways.
(v) In case of emergency, it helps to find the nearest hospital or medical aid.

The components of maps are:
(i) Symbols: Symbols are used on maps because it is not possible to show all details of an area as they actually are. These symbols make it easier to draw maps and also, to understand them.
(ii) Direction: There are four main directions i.e. East, West, South and North, known as the cardinal directions. Maps easily help us to locate direction on the given surface, because northern direction of a map is always marked as 'N'.
(iii) Distance: With the help of scale, large areas can be shown on a small scale map.

The differences between sketch and plan are as follows:
Sketch It is a drawing based on memory and spot observation and not to scale. Sometimes, a rough sketch is required for an area to tell, where a particular area is located with respect to other places. Suppose you want to go to your friend's house and you don't know the way, then your friend may make a rough sketch to show the way to his house. Such a rough drawing is called a sketch map.
Plan: Plan of an area consists of details about length and breadth of a particular location. A plan is a drawing of small area on a large scale or in other words, a drawing drawn to scale is called plan.

There are three components of maps:
(i) Distance A small distance on paper represents a large distance on the ground through a scale.
(ii) Direction Most maps contain an arrow marked with the letter 'N' at the upper right hand corner. This shows the North direction. By knowing one direction, other directions can be found out.
(iii) Symbol: Symbol is the third important component of a map. It is impossible to draw exact size of different features such as buildings, roads, bridges, trees, railway lines or a well on a map, so they are shown by using certain letters, shades, colours, pictures and lines.

A map is a representation or drawing of the earth's surface or a part of its area drawn on a flat surface according to a scale. There are different types of maps.
Some of them are as follows:
(i) Physical maps Maps showing natural features of the earth such as mountains, plateaus, plains, rivers, oceans etc are called physical or relief maps.
(ii) Political maps Maps showing cities, towns, villages and different countries and states of the world with their boundaries are called political maps.
(iii) Thematic maps Maps with specific information like road maps, rainfall maps, maps showing distribution of forests, industries etc are known as thematic maps.