For thousands of years, wool has been a valuable fibre for humans. Today, wool remains an essential fibre in the textile industry and is suitable for a wide range of applications because of its unique properties and versatility. In addition, wool is renewable and biodegradable making it a sustainable choice for technical textiles. However, wool is susceptible to moth damage. This is caused by the moth larvae that feed on the keratin protein present in wool fibres. Therefore, mothproofing methods are necessary to protect wool products. This review aims to provide a comprehensive understanding of wool and its different applications. Wool's chemical composition and structure are discussed in addition to its unique properties and world production. This is followed by a section that highlights the different applications of wool ranging from apparel to technical textiles as well as the numerous insect-proofing treatments of wool. A growing interest in wool powder applications has led researchers to explore various methods for its preparation. In this context, the review reports on developments in novel and emergent mechanical methods of preparing wool powder and its potential applications.