Symbiosis in nature refers to a close and long-term interaction between different species. It can be categorized into three main types: mutualism, where both species benefit; commensalism, where one species benefits and the other is neither harmed nor benefited; and parasitism, where one species benefits at the expense of the other. Symbiotic relationships are common in nature and play a crucial role in shaping ecosystems and maintaining biodiversity. Examples include the relationship between bees and flowers, where bees benefit from nectar while helping in pollination, and the relationship between parasites and their hosts, where the parasite benefits while causing harm to the host.