GroupDocs.Viewer is an HTML5-based document viewer that allows developers on different platforms seamlessly display over 50 different document types, including PDF and Microsoft Office, from within their web-based applications and websites. GroupDocs’ Marketplace team has developed modules that allow Drupal developers integrate GroupDocs.Viewer into their websites. In this post we’d like to share key features of GroupDocs.Viewer along with different integration options available for Drupal. GroupDocs.Viewer is a multi-format document viewer designed based on the client-server architecture.