Human milk oligosaccharides (HMOs) are complex carbohydrates naturally found in human breast milk. Comprising a diverse and unique group of over 200 structures, HMOs play a crucial role in supporting the health and development of infants. While not directly digestible by the infant, HMOs serve as prebiotics, promoting the growth of beneficial bacteria in the infant's gut, which is vital for the development of a healthy microbiome. Additionally, HMOs have been associated with various health benefits, including immune system support and protection against pathogens. The composition of HMOs in breast milk is dynamic, adapting to the specific needs of the infant at different stages of development. Recognizing the importance of HMOs, there is ongoing research to replicate their structures in infant formula, aiming to provide non-breastfed infants with some of the unique benefits associated with breast milk consumption.