The full form of LLDPE is Linear low-density polyethylene.

What  is the difference between the various polyethylene sheeting liners when someone specifies HDPE over LDPE, or LLDPE over MDPE for example? In the simplest terms, each liner will vary by its thickness and its flexibility.  The main difference between the different types of plastic is the way their cellular structure, or molecules bond with each other, and how tightly they are formed.

Linear Low Density Polyethylene (LLDPE) is the most flexible of the plastic sheeting films. LLDPE is blended form of LDPE where the film has much more flexibility, tensile strength, and more conformability. It is more pliable and softer. LLDPE is used for pond liners or blended into other films to give them more flexibility and extra strength. LLDPE is used for films that need a tremendous amount of strength to absorb impacts while not tearing or puncturing. An example of this is a carpet plastic film that adheres to the carpet. It is strong enough to withstand foot traffic, even from stiletto high heels! The molecules all line up and strongly hold together as the film is stretched. The most common thickness range is from 0.5 mil to 40 mil in flexible plastic sheeting.