Alias is a high end NURBS modeller that excels in creating and editing freeform surfaces. In its higher end, more expensive versions, it has the ability to produce Class A surfaces, necessary for automotive design and similar fields. It is especially useful for designers who want to model freeform, organic surfaces by eye, tweaking the surface as they go. Alias is less well suited to creating regular, geometric objects than freeform ones, although it still has plenty of geometric capabilities built in, including basic Boolean operations. It is used more for concept design work than for production work.
Because it dates back to its original use on Silicon Graphics workstations in the 1990s, which had a three button mouse but no scroll wheel, unlike modern mice.
Can I render with Alias?
Yes you can. Alias has built in lighting, materials and rendering capabilities. While it won't replace a more powerful, dedicated rendering engine like Vray that can produce super high quality renders and animations, Alias is still capable of producing good quality renderings.
What if I want better quality renders and animations?
You can import your Alias model into 3ds Max, where it can be rendered and animated to an extremely high level of quality. Alias and 3ds Max are now owned by the same company (Autodesk), so there is a reasonable degree of compatibility between the two programs.