 Map projection actually is the true representation of the longitude and latitudes of the globe. So the network of latitudes and longitude is called the gratitude. So when we are drawing the map over a piece of paper, the map projection is very important. Map projection varies with size and location of different areas on the earth's surface. Now the globe is the true representation of the earth which is divided into various sectors by the lines of latitudes and longitude. This network is called gratitude. Map projection is a systematic drawing of parallels of latitudes and meridians of longitudes on a plain surface for the whole earth or as a part of it on a certain scale so that any point on the earth's surface may correspond to that on the drawing. So like this, this slide represents the three major projections. So this area is for equatorial zones or we can add here the tropical region as well. So this projection is used for the middle latitudes which are actually at the center of the globe, not only in the northern hemisphere but in the southern hemisphere also. So this projection which is actually the zenithal projection we can use for the mapping of the polar areas. So the north pole or you can say here from 70 degree north to 90 degree north same is the case with the sun hemisphere the 70 degree south to 90 degree south. In other word denotes the preparation of graticules on a flat surface. Mathematically the term projection means the determination of points on the plane as viewed from a fixed point. As we have already discussed that on the globe the meridians and parallels are circles. When they are transferred on a plane surface they become intersecting points or you can say the lines in curved or straight. In this slide we are examining if you stick a flat paper over the globe it will not coincide with it over a large surface without being creased. So here the paper is actually flattened over the polar areas. Now here the paper is actually at the side of the globe but touches the middle at shoot and in this area these sides are actually touches the tropical regions. The paper will touch the globe only at one point so that the other sectors will be projected over the plane in a distorted form. So like here the areas which are beyond the tropical region become distorted why because lines of longitude and latitudes are not in a same position as we have over the earth's surface. The amount of distortion increases with the increase in distance. The majority of our projection represents an arrangement of lines of latitudes and longitude with some principles so as to minimize the amount of distortion. With the help of mathematical calculation true relation between latitudes and longitude is maintained. So here we have the projection which is used for the polar areas. So the map shows the areas which are closer to the pole and this actually area is North Pole. So the area which is around the northern pole are the North American, the northern part of North America which actually has the country named Canada, the northern part of Russia and the northern part of Europe. So these areas can be truly pictured in azimuthal projection or zenithal projection. So technique here we can use the paper can be placed over the north of the globe. Now zenithal and conical projections are commonly used for middle latitudes and polar areas. While cylindrical projections are referred for equatorial lands projection also varies with the purpose of the map while transferring the globe on a plane surface. Some facts should be kept in view. Preservation of area, number two preservation of shape, number three preservation of bearing. Bearing means the distance and directions. So with these three components we can make a map perfectly. So keep in mind that the area shape and bearing must be restored. Now these are the types of the zenithal projection. The first one called the nomenic projection. So here the light is coming from the center of the earth and it truly picture the areas which are closer to the pole. Second most important projection in zenithal type is stereographic. Now in stereographic projection the light is coming from the south pole and again it truly represents the area which is closer to the north pole. Now the third main type of the zenithal projection is orthographic. In orthographic all the lines of longitudes and latitudes are actually giving the true directions from the equator and giving the picture of the north pole. Again this is a true picture of the three major types of zenithal projections. Here we have the shape of each and every projection. Now nomenic projection is totally different from the rest of the projections. Why? Because it has different rays which are coming from the center to the each and every lads and longs of the globe. Now in stereographic you have the same thing but in different positions of longitudes and latitudes and again in orthographic projection the areas which are closer to the equator are actually have distance or interval between the two latitudes are smaller than the interval which is closer to the poles are larger. So here we have again the one of the best zenithal projection which can be used for the polar areas which represents the true picture of the poles. Again this is one of the beautiful nation of the nomenical projection. So here we can describe the area that the areas which are closer to the poles are truly represented why because of the lines on latitudes are equally spaced. So these areas are truly pictured but the areas which are closer to the equator here the distance is increased so that's why is not the true picture of the land. So this picture shows or this projection shows that the polar areas are truly represented on a nomenic projection. Here we actually discussed that the projection which are used for the polar areas are actually very important for the making of the true picture of the of the countries which are closer to the pole like in North America the nomenic projection can be used for Canadian islands.