The primary function of a spreadsheet application is to organize, analyze, and store data in a tabular format. Users can input numbers, text, and formulas into cells arranged in rows and columns. This allows for complex calculations, data visualization through charts, and ease of manipulation of data sets. Spreadsheet software, such as Microsoft Excel or Google Sheets, is widely used in business, finance, and education for tasks like budgeting, forecasting, and statistical analysis due to its powerful functionality and user-friendly interface.