When it comes to pest control, there are two main categories: chemical and biological. The word pest can actually refer to bacteria, viruses, or insects that bring disease or transmit infection. It can also refer to animals or vertebrates that kill man-made objects or crops. Common vertebrates, like mice, birds, and snakes, can be classified as pests when they eat man-made food or destroy crops. Plants, like weeds and fungi, can also be pests, particularly if they kill food or store food in their leaves or tunnels.
Chemical control of pests is the use of chemicals to get rid of pests, whereas biological control of pests is the use of microorganisms to get rid of pests. A few common chemical insecticides are pyrethroids, organophosphates, sulfoxides, lindane, and carbaryl. There are many more, including some that have been banned because of the health risks they cause. Other chemicals used are not as well known as the traditional insecticides but still pose risks. The most widely-known example is the weed killer Chlorine.
Biological exterminators work by putting microorganisms in water that kills them. They can be mixed with salicylic acid to get rid of weeds. There are a variety of different methods, but all of them are targeted at removing pests from the environment. Many people feel that it is better to use a combination of methods to ensure the best possible control of any pest.