lifelines of national economy

Now days we are using differnt modes of Taransport to move from one place to another place for carrying goods and people, but in earlier days there were very few modes of transports were available.Nowdays we are using basically these three types of transport means.(1)Landways (2) Waterways and (3)Airways.In landways we use roadways, railways,pipelines.In waterways we use inlandwaterways and sea routes.And in airways we use domestic and international airways.roadways are cheaper and for short distance,railways can carry heavy goods and are cheaper too, pipelines are used to carry goods and it is also a cheaper way to carrying goods from long distance.inlandwaterways are used within the countryside and sea routes are used to trade and to carry people to far distance and countries.domesticairways are used within country and internatinaol airways are used to cover the distance between countries.what do you think which mode of transport is cheaper and commnly used by the people.i will really happy to know your views about the chepest mode of transport.