Both Free 3DelightNSI  and 3DelightNSI come with the following components:

Plug-ins
3Delight for MayaOur proprietary rendering plug-in for Autodesk® Maya®.
→ User's Manual
3Delight for HoudiniOur proprietary rendering plug-in for Side FX's Houdini.
(documentation dimming soon)
3Delight for Cinema 4DOur proprietary rendering plug-in for Maxon Computer's Cinema 4D.
→ User's Manual
3Delight for KatanaOur proprietary rendering plug-in for Foundry's KATANA. Note that 3Delight is built-in KATANA free of charge for interactive renders. For this reason, 3Delight for Katana is not included as part of the Free 3DelightNSI package.
→ User's Manual
Standalone Tools
renderdl

The command line NSI renderer. This program reads a binary or ASCII-encoded NSI files and outputs an image.
→ Documentation

3Delight Display

An advanced image viewer offering several unique features: image layers presentation in contact sheet form, thumbnail view of previous renders and easy A/B comparaison, graphical presentation of rendering statistics, real-time light mixer and user friendly tools to inspect images in details.

* The application is named i-display for launching using the command line.

oslc

The Open Shading Language compiler. It can be used to compile custom OSL shader nodes both for Maya's HyperShade and Katana.

* The compiler is provided with the package for convenience and is built from the main source tree without modifications.

tdlmake

The texture optimizer. This program reads a number of input image files and produces a TIFF optimized texture for the renderer.
→ Documentation

* 3Delight now automatically optimize textures if they are not. So no user action is necessary in the general case. Optimizing textures by hand prior to rendering could potentially save a little bit of time at render start.

Libraries
lib3delightA library that can be linked to other applications to render images. The library implements the NSI API.