Bird species are groups of birds that share common characteristics, such as physical traits, behaviors, and habitats. There are approximately 10,000 different bird species worldwide, ranging from the tiny hummingbird to the large ostrich. Each species has unique adaptations that help them survive in their specific environments, whether in forests, wetlands, or deserts. Bird species are classified into families and orders based on their evolutionary relationships. For example, the sparrow belongs to the family Passeridae, while the eagle is part of the family Accipitridae. Understanding bird species is essential for conservation efforts and maintaining biodiversity in ecosystems.