Brightness is associated with the brilliance of colors and the flexibility to present under many conditions. At 600 lumens, you may need a very dark room to see your projected image clearly. Shaded or dimly lit rooms may require more than 1000 lumens for adequate imaging. When being used for visually challenged individuals, a high-level of brightness may be vital. Portable projectors may tend to be less bright than standard desktop multimedia projectors.
Many models come with multiple ports.
Data ports for connection with a PC or Mac are very common. With desktop computers, the cable that connects to your monitor from the computer is what goes into the projector. There are adapters that will allow you to see the same image on both your desktop monitor and the projector at the same time. With a notebook computer this becomes easier as there is already an extra monitor port on most computers. So all you have to do is run a cable from your notebook to the projector.