LEGO Digital Designer was developed by the Lego Group as a design software for Windows and Mac OS X computers. It is offered as free software to allow creators to build models using virtual LEGO bricks. Designers will find that the user interface and user experience is similar to computer-aided design in that instructions and a box design will be offered to users. The platform also works together with the LEGO Design by ME website where you will find additional instructions and completed boxes. Each designer can take a screen capture of their finished product as well as store the models in an exclusive LDD file extension.