RadSpreadStreamProcessing is part of the Telerik Document Processing libraries. The full documentation for this component is available at http://docs.telerik.com/devtools/document-processing/libraries/radspreadstreamsprocessing.
RadSpreadStreamProcessing is a library that allows you create big spreadsheet documents and export them to the most common file formats with a great performance and minimal resources.
Some of the features you can take advantage of are:
Export to XLSX or CSV files
Styling and formatting cells
Hidden rows and columns