The biggest challenge with recycling plastic is you need to pay attention to what type of plastic it is.

The biggest challenge with recycling plastic is you need to pay attention to what type of plastic it is. Certain types can be recycled easier than others.

To find out what kind of plastic the drinking bottle you just used is made of, try looking at the bottom of the container. There should be a number imprinted on it surrounded by a triangle. This is accompanied by the resin code of the type of plastic it is. Here is a quick list of the different types of plastics or resins.

No. 1: Polyethylene terephthalate, by far the easiest plastic to recycle, is used for soft-drink, water bottles, medicine containers and frozen dinner trays. This type of plastic is commonly recycled into winter clothing, such as fleece and also into several types of rope. Code: PET, PETE

No. 2: High-density polyethylene is used for detergent bottles, milk jugs, food jars, various toiletry containers, household cleaner bottles, salad dressing and cooking oil bottles, condiment containers and most retail/grocery bags. If a plastic bag is recyclable, it will have the code stamped either on the side or bottom of the bag. Code: HDPE

No. 3: Polyvinyl chloride or vinyl is used to make PVC pipes (cold water pipes), house siding, carpet backing, sealing strips in windows, wire and cable sheathing, film, floor coverings, medical tubing and blood bags. Abbreviation: PVC or V

No. 4: Low-density polyethylene is used for dry-cleaning bags, fresh-produce bags, bread bags, plastic newspaper bags, zip lock bags with hardware removed, cereal box liners, plastic shipping envelopes, case wrapping (snacks, water bottles etc.) as well as packaging for furniture, electronics, paper towels, tissue paper, napkins and diapers. Code: LDPE

No. 5: Polypropylene is found in everything from flexible and rigid packaging to large molded automotive and consumer products. It also makes bottle caps, yogurt cups, some types of toys and drinking straws. Code: PP

No. 6: Polystyrene is also known as Styrofoam. Commonly used as packing peanuts, in packaging for various electronics and in various containers, lids, cups and trays. Code: PS

No. 7: Other plastics. There are several types of resins categorized in this type. The most common, high-performing polycarbonate Bisphenol-A (BPA) plastic can be found in protective eye wear, sports equipment, electronics, baby bottles, Nalgene sports bottles and other food containers such as Rubbermaid and Tupperware. Code: OTHER

Note: The Society of the Plastics Industry (SPI) introduced its resin coding system in 1988 to better facilitate recycling with the least amount of waste.