Composite materials, often shortened to composites or called composition materials, are engineered or naturally occurring materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or microscopic scale within the finished structure.
A common example of a composite would be disc brake pads, which consists of hard ceramic particles embedded in soft metal matrix. . Another example is found in shower stalls and bathtubs which are made of fibreglass.

There are ways that you can protect metal surfaces from corrosion, thereby increasing durability and wear of a product with metal parts:

1. Install copper or copper alloy plumbing properly underground to prevent soil corrosion. Poor drainage and moisture are major factors contributing to the corrosion of copper pipelines. A loose layer of backfill such as limestone or pea gravel should be put down in the trench before laying copper pipes.

2. Clean and dry the blades of garden tools after each use. This removes moisture. Wash away soil from shovels, hoes, and rakes before storing away in a cool, dry location. Do not leave tools outside where they can get wet.

Corrosion is not always undesirable. One particular example of the usefulness of corrosion is its effect on aluminum. When oxygen is present (in the air, soil, or water), aluminum instantly reacts to form aluminum oxide. This aluminum oxide layer is chemically bound to the surface, and it seals the core aluminum from any further reaction.

Materials which do not allow the transmission of light are called opaque. Many such substances have a chemical composition which includes what are referred to as absorption centers. Many substances are selective in their absorption of white light frequencies. They absorb certain portions of the visible spectrum, while reflecting others. The frequencies of the spectrum which are not absorbed are either reflected back or transmitted for our physical observation. This is what gives rise to color. The attenuation of light of all frequencies and wavelengths is due to the combined mechanisms of absorption and scattering.

Recycling involves the collection of used and discarded materials processing these materials and making them into new products. It reduces the amount of waste that is thrown into the community dustbins thereby making the environment cleaner and the air more fresh to breathe. To reuse is to use an item more than once.

Biodegradable plastics from natural materials, such as vegetable crop derivatives or animal products, sequester CO2 during the phase when they're growing, only to release CO2 when they're decomposing, so there is no net gain in carbon dioxide emissions, except those caused by the intensive farming process