While there are many different types of plastics, not all of them can be recycled and some of those that can be recycled may not be eligible for curbside pick-up or accepted at your local recycling location. To find out which types of plastic you can recycle in your area, you'll have to contact your local municipal offices or recycling centers. Of the types of plastic that can be recycled, it is critical that they be recycled with their own kind because a small amount of the wrong type of plastic can ruin the melt. Therefore, sorting plastic is a critical part of the recycling process.

To help identify and sort recyclable plastic, the American Society of Plastics Industry developed a standard code, a code used in places other than the United States as well. This code simply identifies the type of plastic used to make that object. It does not indicate whether recyclable plastic was used to make that piece, nor does it indicate whether that type of plastic can be recycled.

The code, generally located on the bottom of the plastic container, consists of three arrows that cycle clockwise and create a triangle with rounded corners. Inside each triangle is a number that identifies that plastic's type. Below each triangle is a combination of letters that correspond to the identifying number located inside the triangle.

There are seven different types of plastic identified by the American Society of Plastics Industry:

1. PET or PETE (Polyethylene terephthalate). This is one of the most frequently recycled plastics by consumers. Containers marked with a "1" include some soft drink bottles, water bottles, plastic peanut butter jars, plastic wrap, and salad dressing bottles.

2. HDPE (High-density polyethylene). This type of recyclable plastic, marked with a "2," is also frequently recycled by consumers. Plastics included in this category include some plastic milk cartons, juice bottles, shampoo bottles, and liquid detergent containers.

3. PVC (Polyvinyl chloride). This type of recyclable plastic, marked by a "3," is less commonly accepted at local recycling centers. It includes some clear food packages, liquid detergent containers, and many construction applications including some traffic cones.

4. LDPE (Low density polyethylene). Marked with a "4," this type of recyclable plastic, is used in some bread and frozen food bags, trash cans, and garbage can liners.

5. PP (Polypropylene). Another plastic commonly used in the automobile and construction industries, plastics marked with a "5" that are also recyclable include some car battery casings, oil funnels, and plastic drinking straws.

6. PS (Polystyrene). Also an uncommon consumer type of recyclable plastic, this type of plastic, marked by a "6," includes some packing foam, plastic cutlery, protective packaging for electronic goods and toys.

7. Other. Some types of plastic marked as "other" or with a "7" can not be recycled as they commonly are made with a combination of the previous six types of plastic, or with a type of plastic other than the six listed above. Containers marked with a "7" that are recyclable plastic include some 3 to 5 gallon reusable water bottles.

The best way to find out which of the seven types of plastics you can recycle is to call your municipal waste management offices or your local recycling center.