A biobank is a large, organised collection of samples, usually human, used for research. Biobanks catalogue and store samples using genetic, clinical, and other characteristics such as age, gender, blood type, and ethnicity. Some samples are also categorised according to environmental factors, such as whether the donor had been exposed to some substance that can affect health. Biobanks play a crucial role in biomedical research, such as in genomics and personalised medicine. Researchers access biobanks when they need samples with similar characteristics for their research studies.