A Microbiologist (from Greek ), is a scientist who studies microscopic life forms and processes or works in the field of microbiology. Microbiologists investigate the growth and characteristics of microscopic organisms such as bacteria, algae, fungi, or some types of parasites. They contribute much to the field by trying to understand and learn about the interaction between these microbes and the environment. Most microbiologists are certified to work in offices and or research facilities such as a laboratory. There, they conduct experiments that help analyze investigation of microbes and their contributions to the field. A microbiologist's work is often repeated or improved in order to establish accurate research. Most microbiologists specialize in environmental, food, agricultural or medical aspects of medical or industrial microbiology including: virology (the study of viruses); immunology (the study of mechanisms that fight infections); or bioinformatics (the methods for storing, retrieving, organizing and analyzing biological data). Many microbiologists use biotechnology to advance the understanding of cell reproduction and human disease. Some microbiologists have contributed to knowledge of pathogens and disease-causing microbes.