In choosing a projector there are several important points to take into account: Resolution, Brightness, Connectivity and Optics. The resolution will determine the level of sharpness and amount of detail that the projected image will have. In the market the most common are: · SVGA , 800x600 pixels. It is the cheapest resolution there is. It is suitable if we only want to show DVD movies , or if our budget is very limited. Example: Nec NP115 · XGA , 1024x780 pixels. It is the most common resolution today. It is the best value for money option, and we can both connect a computer and make presentations as well as watch movies at home. · WXGA , 1280x800 pixels. It allows projections in High Definition and panoramic format . It's perfect for both movie viewing and computer connection, providing more detail and space than other resolutions. Example: W8. The luminosity or lumens will indicate the power of the lamp: the more lumens the projector has, the brighter the image will be and we can make a larger screen with more ambient light. With a 2500 lumen projector (such as Epson X8) we can make a screen 2 meters wide and project without having to darken the room . With a 5000 lumen projector (such as Nec NP3250) we can reach screen sizes from 3 to 5 meters wide (even more if it is for cinema). The most common connections for projectors are the following: · VGA : It is the most widespread and will be used to connect the computer to the projector. The vast majority of projectors come with a VGA connector and cable. · HDMI : It is a high definition digital connection. This connection is ideal for watching High Definition movies, without quality loss. Both Epson X8 and W8 are projectors with HDMI . · Composite Video : it is a very common connection to connect videos and DVDs. Being an analog connection, it provides a medium quality image (especially with long cables). · In addition, in some models we can connect a USB memory, multimedia disk, mobile phone, or camera to make a photo slide show and presentations without a PC . The optics of a projector have two basic parts, the zoom that will allow us to make the screen bigger or smaller as we want and the focus that will allow us to focus the image so that it does not appear blurry. Using a projector is very easy : we will simply connect the corresponding cable, and the projector will automatically detect the signal and start the projection.