Cura is a project which aims to be an single software solution for 3D printing.
While it is developed to be used with the Ultimaker 3D printer, it can be used
with other RepRap based designs.

Cura helps setting up an Ultimaker, shows the 3D model, allows for scaling /
positioning, can slice the model to G-Code with editable configuration
settings, and send this G-Code to the 3D printer for printing.