what are the advantages and disadvantages of travelling by air,sea and land ?

please i want your help
i want write a report about travelling by air,sea and land and i did not find any thing in about it googel or yahoo.
can you please helpme and give me some sources about the advantages and dis advantages of travelling by air,sea and land?

AIR ADV
No traffic

AIR= NO TRAFFIC, FASTEST. COSTS A LOT OF MONEY (BAD)
SEA=NO TRAFFIC, GO PLACES THAT CARS CAN'T GO. BAD WEATHER IS VERY DANGEROUS (BAD)
LAND=PLACES WHERE BOATS CAN'T, FASTER FOR SHORT DISTANCES, NOT AS MUCH MONEY. TRAFFIC (BAD)