Teachers have a variety of options for connecting their MacBook to a projector depending on the type of projector and network environment.
The simplest and most reliable method is to connect directly to the projector via an adapter or “dongle” that plugs into your MacBook. Current MacBooks support adapters that connect to the mini display port or thunderbolt port (pictured below). Depending on your projector, you would choose either a VGA or HDMI adapter.
VGA sends video signal only to the projector. HDMI can carry video and audio to a projector. Chances are you have either one or both. The adapters or “dongles” for your MacBook are pictured below. I typically stay with the ones sold in the Apple Store. You tend to get what you pay for. Less expensive adapters, in this author’s opinion, do not last as long. Also, be wary of HDMI to VGA converters. You tend to get what you pay for in terms of quality and reliability. Audio is another consideration since HDMI carries an audio frequency and VGA does not.
One additional consideration when physically connecting to a projector is Mirroring. Mirroring is simply the term Apple uses to indicate that what you see on your MacBook, you will also see projected on the screen. With mirroring is on both images are the same. With mirroring off, one screen or the other will look blank, but what is really happening is that the additional screen is simply another desktop. Go to System Preferences –> Displays –> Arrangement to set mirroring options on your MacBook.
Part 2 of this article will look at ways to project your MacBook wirelessly using Apple TV or apps like Reflector.