interactive whiteboard!
An interactive whiteboard is a board digital, in which the teachers explain the lessons to the students. Is generally an interactive type of computer screen.
Interactive whiteboards typically require a computer to generate the display via a projector. Typical software mimics is the computer's mouse and keyboard.
They are used in many classrooms, business presentation and workgroup.
The interactive whiteboard is connected to a computer through a wired medium (USB, a serial port cable) or wirelessly (Bluetooth).
They are particularly useful with interactive applications, such as presentation software (e.g. Microsoft PowerPoint), Computer-aided design (CAD) packages, and others.
In my school (escuela2) we have two interactives whiteboards and they are very useful to see films or works.

the information is from: wikipedia.org : http://en.wikipedia.org/wiki/Interactive_whiteboard