From 1960, within a period less than ten years, as a result of development of technology , a revolution occurred in transportation especial shipping and it influenced the main commercial routs this revolution has changed the view of shipping even in developing countries. This revolution is named UNITIZATION and its purpose is transportation of small pieces in standards packing and in a unutilized form by mechanical devices such as crane and etc. from vessel in to wagon or truck and vice versa and delivery it to the receiver at destination. Now a day developing countries try to use unitization in order to over come the shipping and port problems. Generally the advantages of this method is : increasing in the volume of shipment, the management of port operations, decreasing the charges and safety of shipments.

The unitization has various aspects which the most important of them are:

PALLET SYSTEM
LASH SYSTEM
SEA-BEE SYSTEM
PRESLUNG SYSTEM
CONTAINERIAED SYSTEM
The usage of each type of these methods depends on type, quantity and the volume of cargo and also geographic position of ports and their facilities.

-TRANSPORTATION SYSTEM OF CARGO BY PALLET:

In international transportation this kind of cargo packing is technically called palletized method which is one of the easiest ways of unitization. Most of developing countries select this way of transportation because it doesn't required to special equipments and great capital. Usual crane can load and discharge pallet in vessel. Although this kind of transportation has a little benefit concerning to others but mostly it is used. [17](See chapter 3 in this section.).

-TRANSPORTATION SYSTEM OF CARGO BY LASH:

Jroom Goldin, 1952, studied about different ways of transportation in order to decrease the time of discharging and loading and lash packing was his suggestion. The project on which today international shipping lines work has 3 basic elements: [17]

A.LASH:

Lash is a metallic cubic rectangle. Its dimension is L/61.6 ft, W/31.2 ft, irrigable area almost 8 ft, vol/19900ftm3 and max weight/377 ton with water proof door. [17]

B.LASH VESSEL:

The differences between this vessel and others are its wide storage doors and having doors for loading and discharging and also having cranes with the capacity more than 500 tons.

C.CRANE:

Lash vessels have a powerful crane for loading and discharging of cargoes. This crane has four hooks same time and move them.

These vessels are spilled the lashes in to the sea without requiring any jetty in harbor. Then small sailings move them to small platforms in deep water. There is no time limitation in discharging of these lashes therefore vessels continue their voyages after discharging of full lashes and loading of empty lashes so they do not wait in port and they are exempted from paying of quay, discharging, loading and overtime work of labors charges. For this purpose the power operation of ports should be increased with investing huge capital and other foundations of land. Anyway the benefits of this kind of packing that have much flexibility in transportation as general goods, pallet, bulk and reefer is as following:
1. Excessive decrease of voyage time.
2. Decrease of investing capital for building of quay and port establishments.
3. Avoiding vessel's delay in ports for any reason avoiding demurrage finally.
4. Quick transshipment of cargo from one vessel to another.
5. Decrease of loss and stealing of cargo.
6. Remove the problems caused by incorrect loadings.
7. Economize in overtime work of labors due to staying of lashes in port instead of vessel.
8. Direct transportation of industrial products from industrial center beside of inland rivers to final destinations.
9. Change of inland platforms besides rivers to international platforms.
Presently this method isn't being used, because of suitable coast feasibilities and establishments and also high volume of trading exchanges and not being the vessels traffics in Iranian ports as using this system caused the jetties to be useless and therefore decreasing the foreign income. So they use unitization.

TRANSPORTATION SYSTEM OF CARGO BY C.B.:

The basic of this system is similar to lash system. Thus this system transport some metallic lashes full of cargo by special vessels and it's principle difference with them is in the volume of lashes and the mechanism of it's crane. Lashes volume in CB system is almost 40000 ftm3. that is double of lashes volume in lash system. Meanwhile it is used from a elevator with 2000 ton power instead of crane 500 ton in CB system. It can leave from sea two barges with 40000 ftm3 full f cargo and put it down in the vessel. Except above mentioned items there is no different in the appearance of them.

TRANSPORTATION SYSTEM OF CARGO VIA SAILDRUM:

It is one of the consolidated transportation manner for liquid cargoes. That is a elastic and contractile net for transporting of motor oil, chemical liquid as asid, alcohol, Petrolia products and another industrial liquids. This net is made of special elastic so it is so light. Their inner layers are resistant against liquid that pour in it. Because of their contractile characteristics, the volume of an empty sail drum is almost 15% volume of a full sail drum. This net is resistant against light, oxide and 65 DF and it can be tolerate up to 30 pound pressure with 500 gallon volume.
The shape of them is similar to cylinder that can be turned easily but usually when they are loaded or discharged from vessel, join some of them together and then attach them with crane. One of the benefits of sail drum is that 15%.