Poser is an application to assist artists in drawing figures. It has expanded to be a graphics application that uses prebuilt 3D models to create scenes of figures and props.
Figures are any objects with moving poseable parts, such as humans, animals and machinery.
Props are objects with no moving parts such as boxes, furniture or buildings.
The program is capable of creating near photographic quality images.
Poser is owned by Smith microsystems. Daz3d has a similar product called Daz Studio which they created to ensure an application for their 3d content.