A plastic bag or pouch is a type of flexible packaging made of thin, flexible, plastic film. Plastic bags are used for containing and transporting foods, produce, powders, ice, chemicals, waste, etc. A plastic bag is a container, usually with a tubular construction, made of flexible plastic film. Bags can be preformed and filled and sealed (or not sealed) later or can be formed at the filling and sealing operation. A pouch is usually a small or moderate sized bag. Bags can be made of many different materials. -Polyethylene is the most common: LDPE, HDPE, LLDPE, etc.

-Polypropylene, OPP. -Coextrusions of multiple layers to improve physical properties and optimize material usage

 -Laminations for better mechanical or barrier properties such as Nylon and LDPE for vacuum packaging

 -Woven plastic fibers, usually oriented polypropylene

-Specialty bag materials such as plasticized PVC (blood bags), Tyvek (sterilized medical supplies), cellophane, etc.

Most are heat sealed together. Some are bonded with adhesives or are stitched. A press-to-close zipper can be used to open and close the bag many times.

Poly Bags and films, Plastic Bin Boxes and Plastic Pallets - are good representetives of this group.