20 computer terms every Mac user should know

Throughout the life of Mac 101, we’ve talked a lot about Apple technologies and terms. But with the gentle persuasion of this column’s readers, I’ve come to realize that—all too often—terms and acronyms that many of us take for granted leave users new to technology scratching their heads. Let’s rectify that now with a meander through some common tech terms.

For many of us, our Mac isn’t a one-stop shop. We routinely attach things like printers, cameras, and external hard drives to it. Below, I discuss the technologies that support such connections.

USB (Universal Serial Bus): This connection standard supports the transfer of data between devices and their peripherals. You’ll find USB connectors on computers, keyboards, pointing devices (mice and trackpads), digital cameras, camcorders, printers, portable media players (such as iPhones, iPods, and iPads), hard drives, network adapters, AV receivers, hubs, music keyboards, microphones, headphones, and just about any other device that can be attached to a computer. USB can also deliver power to devices that don’t demand a lot of the stuff.

A regular USB connector appears at one end of this cable (the upper end in the photo), and a Micro-USB connector appears at the other end.

There have been three major working USB specifications—USB 1.1, USB 2.0, and USB 3.0. The main difference between them is speed. Newer versions of USB are faster than their predecessors. USB is backward-compatible, so you can use a device designed for USB 2.0 in combination with another device using USB 3.0 ports.

Three styles of USB connectors are available: the standard rectangular one you find on your Mac; the trapezoid-shaped mini-connector that some digital cameras and hard drives rely on, and the tiny Micro-USB connector that you would use with a modern Kindle reader.

FireWire: FireWire (also known as IEEE 1394) is a technology for connecting compatible devices. It was designed for situations where fast transfer rates are crucial, including computers, storage devices, audio interfaces, and video gear such as camcorders and video interfaces.

A FireWire 400–to–FireWire 800 cable.

Although higher-speed FireWire standards exist, you’ll most often encounter FireWire 400 and FireWire 800 connectors. FireWire 800, the newer standard, supports much faster speeds than FireWire 400 does. FireWire 800 is backward-compatible with FireWire 400 devices. Each bears a unique connector. The typical FireWire 400 connector is oblong, rounded on one end and flat on the other. The FireWire 800 connector is rectangular. You can also find mini FireWire connectors, which are small and have a trapezoidal shape. Recent Macs that have a FireWire connector use FireWire 800.

Apple's Lightning cable.

Lightning: This is the proprietary connector found on today’s most recent iPod touch, iPhone, iPad, and iPad mini models. It replaces the 30-pin dock connector found on earlier iOS devices and iPods. Unlike that connector, the Lightning connector works regardless of which side is facing up. Like the 30-pin connector before it, the non-Lightning end of the cable sports a USB connector and lets you transfer data as well as power to an attached device.

Thunderbolt: Thunderbolt is today’s faster transfer scheme. Unlike FireWire or USB, it can handle both data and video connections simultaneously. You can string a single Thunderbolt cable between your Mac and, say, Apple’s Thunderbolt Display, and use that connection to view the Mac’s video on the display while using the USB, FireWire, Thunderbolt, and ethernet connectors on the back of the display to attach other devices to your Mac.

Thunderbolt is up to 20 times faster than USB 2.0 and up to 12 times faster than FireWire 800. You can connect as many as six compatible devices from a single Thunderbolt port. With a compatible adapter, you can connect USB, FireWire, and gigabit ethernet devices to a Thunderbolt port. The following Macs have Thunderbolt ports:

MacBook Pro (Retina, 13-inch, late 2012)MacBook Pro (Retina, mid-2012)MacBook Pro (early 2011) and laterMacBook Air (mid-2011) and laterMac mini Server (mid-2011) and laterMac mini (mid-2011) and lateriMac (mid-2011) and later

There are many ways to move video signals around. Here are the video standards you’re most likely to encounter.

With this $39 kit, you can send video and audio from your 30-pin iOS device to a composite-compatible device.

Composite: Composite video is an analog standard that supports 480p video (which has a resolution of 720 by 480 pixels). Composite cables most often use three RCA-style connectors. The red and white connectors are for right and left stereo audio, respectively, and the yellow connector is for video.You'll find these connectors on old VCRs, videogame consoles, TVs, AV receivers, and camcorders. Macs haven’t had composite video connectors on them for a very, very long time—and even when they were available, they were found only on “AV” Macs. Apple doesn’t sell composite adapters for the Mac, but you can purchase such an adapter for your 30-pin iOS device in the form of Apple’s $39 Apple Composite AV Cable.

Component: Component video is another analog video standard, but one of higher quality than composite. Component cables typically have three RCA connectors colored red, green, and blue. In household use, it supports up to 1080p resolution (1920 by 1080) and offers a better picture than composite video. Some video cards offer component connectors, but you won’t find them natively on Macs.

A Mini DisplayPort connector.

Mini DisplayPort: Introduced with late 2008’s Mac models, Mini DisplayPort supports digital video only and offers resolutions of up to 2560 by 1600. The connector is a small rectangle with two rounded corners and looks exactly like a Thunderbolt connector. (In fact, you can use a Mini DisplayPort connector in a Thunderbolt port.) Adapters are available for converting Mini DisplayPort to VGA, DVI, or HDMI signals.

DVI (Digital Visual Interface): The DVI connector can act as both an analog connector and a digital one. It supports three kinds of connectors—DVI, Mini-DVI, and Micro-DVI—and offers resolutions of up to 2560 by 1600. You can identify these rectangular connectors by their two blocks of straight round pins next to a larger thin rectangular pin. DVI connectors were found on Macs in the 2000s until 2008, when Apple replaced them with Mini DisplayPort connectors.

HDMI (High-Definition Multimedia Interface): Found on today’s HDTVs and AV receivers, HDMI connectors are also part of today’s Mac mini models and will be available on the Mac Pro that Apple intends to release in fall 2013. HDMI supports resolutions of up to 2560 by 1600 at 75Hz and up to 4096 by 2160 at 24Hz. An HDMI connection includes both audio and video.

VGA (Video Graphics Array): This is a large, 15-pin trapezoidal connector found on older computers and inexpensive video cards. Such connectors can still be found on some modern TVs and computer monitors. VGA is another analog standard and supports resolutions of up to 2048 by 1536. Macs haven’t had VGA connectors for quite some time, but you can attach a Mac to a VGA monitor, TV, or projector by using an adapter compatible with your Mac’s video connector.