Open systems are systems that interact with their environment, exchanging information, energy, or materials. They are characterized by their ability to adapt and evolve based on external influences. Examples of open systems include ecosystems, economies, and organizations, where inputs from outside sources contribute to their functioning and growth. In contrast to closed systems, which do not exchange matter or energy with their surroundings, open systems are dynamic and responsive. This adaptability allows them to thrive in changing conditions, making them essential for understanding complex phenomena in fields like biology, economics, and engineering.