Zero-shot learning (ZSL) is an innovative machine learning technique that enables models to classify data from previously unseen classes by using semantic relationships or attributes learned from known data, reducing the need for extensive labeled datasets. This approach is particularly beneficial in fields like computer vision and natural language processing, where labeled data is often limited. ZSL models use a variety of methods, including attribute-based and semantic embedding techniques, to bridge the gap between known and unknown classes. Generalized Zero-Shot Learning (GZSL) extends this capability by training models on both known and unknown classes, often using generative methods like GANs and VAEs to create training samples. Despite its advantages, ZSL faces challenges such as hubness, semantic loss, domain shift, and bias, which researchers continue to address. Notably, ZSL has practical applications in tasks like image search, captioning, and object detection, and remains a promising area of AI research with the potential to streamline data annotation and enhance model generalization across diverse domains.