Model organisms are species that are studied extensively in scientific research due to their usefulness in understanding biological processes, genetics, and development. These organisms are often selected for their ease of breeding, short generation times, genetic tractability, and similarity to humans or other organisms of interest. Some common model organisms include fruit flies (Drosophila melanogaster), nematode worms (Caenorhabditis elegans), yeast (Saccharomyces cerevisiae), mice (Mus musculus), and zebrafish (Danio rerio). These organisms have been instrumental in advancing our understanding of fundamental biological processes, such as embryonic development, gene regulation, and disease mechanisms. Model organisms are used in a wide range of research areas, including genetics, developmental biology, neuroscience, and evolutionary biology. Studying these organisms allows researchers to make important discoveries that can be applied to other species, including humans, and help to drive progress in various fields of science.