There are different types of clear plastic wrappings and each has specific properties. To be sure of getting the right kind of bag for your purposes you need to know the difference between "cello" and "poly" bags.

Cello Bags

Cellophane is made from cellulose, found in the cell walls of green plants. Cellulose makes up at least a third of all plant matter, but wood and cotton are the main sources for industrial purposes as they contain up to 90 percent. Cellophane is resistant to water and odors and it has a distinctive clear appearance.

Poly Bags

There are two types of poly bags, both by-products from the petro-chemical industry and they have slightly different physical characteristics: Polyethylene is very flexible, folds easily and is heat seal-able. It is, however, porous to moisture and vapor. Polypropylene is stiffer by comparison and gives better protection against vapors and moisture.

Different Applications

Cellophane is generally preferred when attractive presentation is required. It has a brilliant and clear appearance and is crackly to the touch. It is ideal for wrapping small items of food or drink as well as bouquets and gift hampers. Because it is nonporous it will preserve freshness and contain odors. It is chemically inert with foodstuffs so will not affect the flavor of what it contains. Poly bags, on the other hand, have a wider range of application, depending upon the thickness used: 1mm protects against dust and is often found on food items in retailers. 1.5mm is the average thickness for food bags and offers more protection. 3mm for heavier items such as tools, light equipment, and furniture.