This is an essential text which gives a contemporary account of various aspects of biodiversity for undergraduate and postgraduate students. Biodiversity is essential for the existence of all living organisms, including humans, and is necessary for maintaining healthy ecosystems. It offers us vital resources such as clean air, freshwater, and nourishing food, as well as medicinal plants and the ability to support future generations. Pollinators, such as birds, bees, and other insects, are particularly important for global crop production, contributing to one-third of total food production. Without them, numerous crops would not exist. Agriculture greatly relies on invertebrates, which are crucial for maintaining soil and crop health. Microorganisms release nutrients that are necessary for plant growth and are passed on to us through the food chain. Marine life also plays a significant role in supporting life on Earth, including our existence. A wide range of plants, microorganisms, and animal species contribute to maintaining healthy ecosystems that provide us with the air we breathe and the food we consume. People value the natural world greatly.