A data analyst helps organizations gain valuable insights from their data by performing key tasks like preparing data, modeling relationships between data, visualizing data in reports to identify patterns and trends, analyzing the data to communicate findings, and managing Power BI assets like reports, dashboards and data models. Data preparation involves cleaning, transforming and profiling raw data to eliminate errors and ensure the data makes sense. Modeling defines how tables relate and metrics are calculated to enrich understanding. Visualization brings the data to life in reports that tell compelling stories to guide decision making.