Iron is an essential nutrient for the growth, survival and virulence of almost all bacteria. To access iron, many bacteria produce siderophores, molecules with a high affinity for iron. Research has highlighted substantial diversity in the chemical structure of siderophores produced by bacteria, as well as remarkable variety in the molecular mechanisms involved in strategies for acquiring iron through these molecules. The metal-chelating properties of siderophores, characterized by their high affinity for iron and ability to chelate numerous other metals (albeit with lower affinity compared to iron), have also generated interest in diverse fields. Siderophores find applications in the environment, such as in bioremediation and agriculture, where emerging and innovative strategies are being developed to address pollution and enhance nutrient availability for plants. Moreover, in medicine, siderophores could be used a tools for novel antimicrobial therapies, medical imaging, as well as in hemochromatosis, thalassemia or cancer treatments. This review offers insights into the diversity of siderophores, highlighting their potential applications in environmental and medical contexts.