PHPExcel is a PHP spreadsheet library used for programmatically reading and writing spreadsheet files in various formats. It utilizes an in-memory spreadsheet model that maps spreadsheet structures to a hierarchy of objects for programmatic manipulation.
The library functions as an Office Open XML processor for generating and manipulating XLSX documents and serves as a reader for extracting data and structure from legacy binary XLS files. It also includes tools for CSV data integration and importing.
The project provides capabilities for automated report generation and spreadsheet data extraction, allowing application data to be converted into portable documents or imported into databases.