DAZ Studio is a free 3D design application--but it probably doesn't do what you think it does. Most 3D design software focuses on modeling objects. DAZ Studio's sister program, commercial Carrara, is a more traditional modeler. SketchUp is great for modeling buildings, Sculptris is for sculpting organic shapes, Silo is for general modeling... and DAZ Studio isn't really for modeling at all. With its heavy emphasis on posing and morphing, using DAZ Studio is almost like playing with dolls or action figures--you take ready-made, beautiful models, and just assemble and pose them to the scene of your dreams, a bit like what you can do with the $250 Poser 3D character design application.
3D design software is notoriously complex, and DAZ Studio goes out of its way to be beginner-friendly. It uses interface presets that toggle parts of the application to suit the user's expertise. The beginner-friendly layout, Hollywood Blvd, uses large panes with lots of thumbnails and a clear, step-by-step workflow to take you from concept to render. The advanced layout, City Limits, collapses the panes by default and reveals the myriad toolbar buttons that inevitably come with 3D design.
What DAZ Studio lacks in modeling tools it makes up for in detailed models and morph controls. The most impressive model included is called Genesis. This is a human model with impressively detailed built-in morphs. When you just put it into the scene, it looks a bit like a featureless, androgynous mannequin. Want it to be a man? Just move a slider, and the anatomy morphs to a more masculine build. Should it be thin? Move another slider, and the whole body subtly loses fat. If you want it to be a body-builder, you can move yet another slider and watch as muscles appear and make for an impressively defined physique.
Genesis also comes with built-in poses, so it's easy to make your character sit or stand. For finer-grained control, you can use DAZ Studio's posing tools. Genesis and other models use inverse kinematics, which means that they have a virtual bone structure that moves in natural ways. If you pull a figure's hand forward, its arm will follow. Pull some more, and the figure will bend its back in a believable fashion. The same sort of control also extends to facial muscles--you can make your Genesis figure lift the outer part of its left eyebrow by moving a slider.
The only problem I've had with posing in DAZ Studio is that it is all too easy to push a character's arm into the floor, or into itself. In other words, when you push a surface against another surface, they intersect rather than collide. This makes it difficult to make your Genesis figure sit astride a lion in a believable way.
Clothing is another important aspect of DAZ Studio: You can dress characters up, and the clothes will automatically morph to fit the character's body shape and current position. Some clothes may not automatically adapt to morphs well enough, resulting in a phenomenon called "poke-through," which means you can see the character's skin poking through the cloth in strange ways. When this happens, DAZ Studio allows you to tweak clothes until they conform well.
For DAZ Studio to work well, it needs detailed models. You can get these from the DAZ online store, which features anything from people and animals, to vehicles, clothes, and environments. Right now, you can access the store using a Web browser, but DAZ Studio 4.5 Beta shows that the groundwork is being laid for accessing your DAZ account from within the application itself. This part isn't ready yet, so I couldn't test it.
DAZ Studio combines complex existing models with an accessible interface, resulting in a fun, simple 3D experience. If you've always wanted to dabble with 3D but creating detailed models and textures from scratch seemed like a daunting task, DAZ Studio can save much of the work and leave you just with the creative parts.
Note: The Download button takes you to the vendor's site, where you can download the latest version of the software appropriate to your system.