# Introduction

This section provides an overview of the Compression folio and describes how it works. See 3DO System Programmer's Reference for complete descriptions of the calls mentioned in this section.

The compression folio provides services that compress and decompress data in a non-lossy manner. The compression quality differs depending on the type of data. Compression ratios range typically from 50 percent up to 80 percent.

The intended use of the Compression folio is to compress data that is being written to NVRAM. It is critical that data being written to NVRAM be as compact as possible because it is a limited resource. The interface to the compression and decompression engine is totally generic, allowing the folio to be used for any data that needs to be compressed.