ZBrush is a digital sculpting and painting application that combines 3D/2.5D modeling, texturing and painting. It is used for creating high-resolution models for use in video games, movies, animation, and 3D printing. It provides users with powerful tools for creating detailed 3D models and textures, and can be used to create realistic characters, creatures, environments, and more. ZBrush allows for a wide range of design possibilities, and a powerful set of sculpting, painting, and sculpting tools. It also includes a unique set of brushes and other tools, allowing for a wide range of creative freedom. The user interface is intuitive and easy to use, and the resulting models can be exported to a variety of formats.
It's free, simpler and has many other uses, but it may not be as powerful as ZBrush in terms of performance or sculpting.