Machine made rugs are made by large machines called power looms. A power loom is electrically automated and controlled by computers. It is woven with a machine- loom that is programmed to the right pattern and runs hundreds of reels, which, by rotation, put the threads in motion. Machine Made carpets are made of 100% acrylic, composition of acrylic and wools/polyester is common as well. Natural wools are more expensive than artificial fibres thus are used less in machine-woven carpets. Further artificial fibres used in machine made carpets are polyester (artificial silk) and polypropylene. Polyester gives shinny look to carpet and makes them look like silky carpets and as they have low fluffing (pilling) similar to acrylic and wool carpets, they have become more popular among some people in spite of the fact that they have less durability. Machine made rugs can be made quickly and usually have a life span of about 20 years or less, depending on the quality and fibre used. For example a high quality machine made wool rug can last for decades if it is well maintained. Machine made rugs are the most cost effective and easy to maintain.