“What is the default file extension for a Microsoft Excel workbook?”

"The .xlsx file extension is the default for Microsoft Excel workbooks introduced with Excel 2007. Based on XML it supports advanced features like macros and large datasets ensuring compatibility across platforms. This format enhances data storage and sharing in business finance and research. Understanding .xlsx is essential for professionals using Excel for data analysis as it ensures seamless file handling and integration with other software optimizing productivity in spreadsheet-based tasks and data management."