A tree is a tall, woody perennial plant with a trunk and branches that support leaves or needles. Trees play a vital role in the environment by providing oxygen, absorbing carbon dioxide, and offering habitats for various organisms. They can be found in diverse ecosystems worldwide, ranging from lush forests to arid deserts. Trees also offer shade, produce fruits or nuts, and contribute to the overall beauty of landscapes. Their longevity and ability to adapt make them essential contributors to the Earth's ecosystem.