A symbiotic relationship is a close and long-term interaction between two different species, where both parties benefit from each other. It's an interdependent association in which one organism provides something that another organism needs or wants. This type of relationship can occur in various forms such as mutualism (both species benefit), commensalism (one species benefits while the other is not affected), and parasitism (one species benefits at the expense of the other). Examples include bees and flowers, where bees collect nectar from flowers for food, while helping to pollinate them in the process; or lichens, which are a combination of fungi and algae living together in a mutually beneficial relationship.