Data analysis is the process of inspecting, cleaning, transforming, and modeling data to uncover useful insights, support decision-making, and solve business problems. It involves identifying trends, patterns, and relationships within datasets to provide a clear understanding of the data. Techniques range from simple statistical analysis to more complex methods like predictive analytics or machine learning. The results of data analysis help drive strategy, optimize processes, and improve overall efficiency in various fields such as marketing, finance, and operations.