Power BI provides a variety of connectors to extract data from numerous sources such as databases, spreadsheets, cloud services, and APIs. By importing and transforming data using Power Query, users can merge and shape data from multiple sources. The data can then be visualized using Power BI's rich set of data visualization options, such as charts, tables, and maps. Using DAX (Data Analysis Expressions), calculations and aggregations can be performed on the imported data. Power BI also offers the ability to create relationships between different tables, allowing for advanced analysis and reporting.