When news of a new Mac notebook leaked two months ago, one of the aspects that seemed most absurd was the omission of multiple ports. Instead, there would be just one hole. Weirder still, it would be USB-C, a format never before seen in a Mac and unfamiliar to most people, as it was only unveiled in production equipment last September.

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Turns out, it wasn't absurd at all. With the new 12-inch MacBook, Apple has gone all in for all-in-one, using USB-C to provide power, display output, and USB connections. Thunderbolt is gone. The SD card slot is gone as well. And the MagSafe component of the power connection has disappeared into very thin Air--I mean, thin MacBook. (Magnets? How do they work?)

Apple says that USB-C adapters can provide HDMI, DisplayPort, VGA, gigabit ethernet, and USB 3.1 support, and can both power a computer and send power to attached peripherals. Notably, ethernet and DisplayPort options aren't included in the current USB-C accessories list at the Apple Store.

But Thunderbolt is the really big loser in the new 12-inch MacBook: USB-C can't support Thunderbolt devices.

In the pursuit of slimness, sleekness, and simplicity--the same goal that brought us Lightning--Apple has seemingly done with Thunderbolt what it once did with FireWire. But is USB-C a worthwhile shift for users? Well, all interfaces are compromises in one way or another, and Apple believes USB-C meets more customers' needs, even as the new interface throws some people off a cliff.

The upside is compatibility, and thus lower costs and more options. USB-C is also a unifying and universal standard that doesn't involve a single company acting as a licensing gatekeeper, the way Apple protects Lightning cables and adapters. USB-C would seem to have a lot to offer, but first we have to get over the hump of newness.

FireWire in the hole!

We've gone through this before, and every iteration brings pain and joy. The pain comes from having to purchase new adapters and figure out the limitations of the new interface. The joy flows from improvements in performance and flexibility, and simplicity in making connections.

The bump from Apple Desktop Bus (ADB, Apple's original serial peripheral standard for keyboards) and SCSI (for hard drives and scanners, among other uses) to USB 1.1 was a big one in the first iMac circa 1998. ADB was slow, required daisy-chaining, and could be finicky. SCSI was fussy as all get out, despite its relatively high speed. (Remember terminators? Self-termination? Numbering devices? Running out of numbers?)

But USB let you plug and unplug, even while devices were in use! Sure, you could leave a hard drive in a weird state by unplugging before it was fully unmounted, but you at least wouldn't fry its circuits by accident.

USB 1.1 was always an intermediate step. At 12Mbps, it was far too slow. and USB 2 wasn't ready when Apple was. FireWire 400's introduction just a year later offered a vast improvement in speed. FireWire 800 doubled that a couple of years after, but despite a path to 1600 Mbps and 3200 Mbps, the standard was mostly single purpose: a way to move data rapidly among storage.

Enter Thunderbolt, the unifier. Originally slated to work over resilient fiber optic cables, allowing low power requirements and long distances, the first release was a bit of a compromise. It used copper wire and could extended only three meters (10 feet) maximum, but could also deliver power, which wasn't part of the optical specification. The first version shipped on a Mac just four short years ago.

The video standard DisplayPort, which has many potential variations of throughput, each of which can support a maximum refresh rate and monitor resolution, was supported as something that flowed over Thunderbolt, allowing forward compatibility. A Thunderbolt connection could support a DisplayPort-equipped monitor. Thunderbolt's first iteration was 10Gbps per channel, allowing an aggregate of 40Gbps (20Gbps in each direction). Thunderbolt 2 doubled that throughput.

But Thunderbolt stalled. While it's available in computers beyond Macs and in peripherals from many companies, it's never become pervasive. The rest of the industry has focused efforts on USB 3. Apple may eat a hunk of the profit in the PC market, but for unit volume among all connections, USB is orders of magnitude higher.

Apple didn't disregard progress on USB, adding USB 3 ports in Mac models that shipped in 2012. But you can only shrink a mini-DisplayPort connector used for Thunderbolt so far. It's got one correct orientation, and it can't easily be used to power other devices via a single port.

Thunderbolt was essentially too expensive to implement on inexpensive devices. It also has licensing rules that deterred some manufacturers. The USB-C adapter format avoids just these kinds of roadblocks.

The USB-C spec is under the control of the USB 3.0 Promoter Group, which doesn't include Apple among the key members that drafted version 3.1, but which engages in no preferential or discriminatory treatment about who may license or use it. Lightning can't support the data rate needed for peripherals, nor the wattage required for a notebook. Nor can it achieve the industry adoption needed for an ecosystem.

Within that worldview, USB-C seems more inevitable than unexpected, and we'll ultimately get used to it.

USB all that you can USB

While USB 3 is a few years old, USB-C only debuted last September, and was clearly designed in part to replicate the advantages of Apple's Lightning connectors. It's slim and reversible. Apple's flavor has a raw data rate of 5Gbps, and passes 29 watts of charge from the included power adapter.

The Dock-to-Lightning transition was painful for iOS devices, because many of us had invested in an ecosystem of devices that relied on the Dock connector. Most of us swapped our iOS device when we got a new iPhone, iPad, or iPod touch (remember those?), and in a home social grouping, would pass down an old model. Lightning meant our stereos and cables and docks wouldn't serve old and new, yet the old devices still had plenty of life in them.

Worse, most people I know with an iPhone have two or more cables, sometimes permanently installed in different places, like a car, or stashed as an extra in a satchel or purse. The early Lightning adapters were $29 for a little stub and $39 for a cable. You could wind up with incompatible audio and other gear, and $150 of cable costs. It annoyed people, and rightly so, because it felt like an upgrade penalty instead of benefit.

But the situation is different with the MacBook, as you won't lose a lot of sunk costs if you're shifting from one Mac laptop to the MacBook. The only interface types you lose are MagSafe and Thunderbolt. If you need Thunderbolt devices, this isn't the computer for you. Your MagSafe adapters, meanwhile, can clearly continue to be used with your older computer, whether you keep using it or pass it on.

USB-C allows bidirectional charging, which changes the cable equation. The new computer ships with just a USB-C charging cable (two meters, $29 sold separately) and a 29-watt power adapter with a USB Type A jack ($49 separately). The charger can power an iPhone or iPad, and ostensibly the USB-C charging cable could be driven by any USB Type A jack--although a 5-watt or 10-watt charger or a 10-watt or 12-watt car adapter will charge it quite slowly. (I was unable to get confirmation on that latter point.)

With a USB-C adapter that splits into multiple interface types, you can charge devices over its USB parts just as if they were part of the computer's hardware. Apple is offering three adapters to start with: a $19 USB-C to USB 3.1 Type A port, into which a regular Type A connector can fit; and $79 A/V adapters, one for VGA and one for HDMI, both of which also sport USB-C charging and USB Type A ports. (It's unclear at this writing if that USB-C charging port can be chained into more adapters, but it seems very likely based on the spec.)

Apple isn't offering gigabit ethernet or DisplayPort adapters in its initial foray, but these adapters should be available soon from third parties. Last year, such adapters were expected in early 2015, and this availability projection may be one reason Apple isn't shipping the new MacBook until April. Its spec sheet says that the MacBook comes with "native DisplayPort 1.2 output," which will support 4K (3840x2160 pixels in dual monitor or mirroring modes), but there's technically no way today to access that stream of video data.

A spec was set last September to encapsulate DisplayPort inside a USB-C to USB-C cable, just like Thunderbolt encapsulated DisplayPort, so we'll likely see some of that in future monitors as well.

The power persists

Thunderbolt isn't dead and USB-C doesn't look like it's going to kill it off soon. Indeed, it seems likely that USB-C will wind up replacing ports on consumer-leaning Macs, like future MacBooks (if 12-inch isn't the only model), Mac minis, and iMacs, while the Mac Pro and MacBook Pro will probably retain Thunderbolt for the highest performance with external drives and other peripherals.

If you're dead set on buying a USB-C machine, make sure you know what you're getting into--especially if you use your laptop as a fully appointed portable workstation like I do. Before ordering, you need to make sure the particular multi-prong adapters you'll need are available, compatible, and affordable.

It could be that Apple is signaling the post-peripheral era, appealing to a new majority of users who really only need USB to charge their machines. The current MacBook's SD Card slot is of little use to an iPhone photographer, for instance.

And with more than 9 hours of battery life, many mobile-first users can comfortably give up their single do-everything USB-C port when they need USB connectivity for, say, a thumb drive. Sure, that USB-C port is also your lifeline to charging power. But the definition of "power" user could be about to change.