The Mac Pro, Apple's new high-tech professional computer, boiled down into a tiny black cylinder, is being released on Thursday, Dec. 19. Here's what you need to know.

It's been a long time coming. Apple's Phil Schiller announced the Mac Pro back in June 2013 at the company's Worldwide Developer's Conference, with the jeer "Can't innovate anymore, my ass!"

Though a bit defensive sounding, it's true; of all the products Apple unveiled in 2013, the Mac Pro was the most radically new.

First, Apple has completely redesigned and reengineered its high-end desktop computer to fit into a chassis with an incredibly small footprint. The black aluminum cylinder is only about 10 inches tall and about six and a half inches in diameter.

When Schiller introduced the Mac Pro for the first time - standing next to the previous generation and looking about a tenth the size - there were audible gasps through the audience.

And despite looking more like a Mac mini than a professional desktop computer (haters immediately trashed the Mac Pro for looking like a garbage receptacle, though I initially thought it looked a little more like an angry little space heater), Apple has packed in some pretty impressive hardware that will make pro users happy.

Hardware

The Mac Pro's CPU offers the next-generation Intel Xeon E5 chipset, with anywhere from four cores to 12, depending on how much you (or your company) are willing to pay. The base model has a 3.7 GHz quad-core Intel Xeon E5 with Apple's overclocking Turbo Boost, which brings speeds up to 3.9 GHz - all transferring over a 40 GB/s third-generation PCI Express connection. The bottom line? Apple promises twice the speed compared to the previous generation of Mac Pros.

Also fitted into the small cylinder are two AMD FirePro GPUs with 2GB of video RAM each (GDDR5), upgradeable to up to 12GB, delivering up to eight times the graphics performance as the previous Mac Pro. Speaking of RAM, the base model comes with 12GB of four-channel DDR3 RAM at 1866MHz, though that can be configured to 64GB. The Mac Pro's storage is also super-fast, as the cheapest Mac Pro comes with 256GB of PCI express-based SSD storage.

This is all geared to make performance-heavy customers like graphic designers and video editors very happy: for example, Apple promises the Mac Pro is capable of "seamlessly editing full-resolution 4K video while simultaneously rendering effects in the background."

Design

Besides looking completely different than any other desktop workstation, the new Mac Pro's cylindrical design was engineered to take advantage of a single, unified triangular thermal core in the center. The core conducts heat away from the CPU and GPUs and distributes it evenly across the core, so that if, for example, the GPUs are working overtime but other parts of the computer aren't, the thermal load is shared evenly across the entire machine. And instead of using multiple heat sinks and fans, there's one fan that pulls air up from the bottom and out the top, making the Mac Pro much quieter than standard desktop computers.

The one criticism of this fundamental redesign of how computers are built is expandability and upgradeability. Pro users need a computer to be high-performance now and in the future, especially considering the Mac Pro costs $2,999 and up (and up, and up - to more than $10K).

The previous generation Mac Pro - though it was large, loud, and basically hadn't changed its clunky chassis in a decade, since the 2003 Power Mac G5 was released - was nevertheless highly expandable. With the new, compact model, tech experts and power users have been worried that Apple is making the prospect of upgrading the Mac Pro as unlikely as adding RAM to a new MacBook Pro with Retina Display (with its RAM firmly, unalterably soldered to the frame).

The reality is that Apple's Mac Pro is upgradeable in a basic way, though, because of the radical design, upgrading options will be more limited than before.

First off, RAM is upgradeable, and the Mac Pro's four RAM slots appear to be easily accessible for plug and play. However, even though the GPUs are based on PCI Express, to fit into the Mac Pro's tiny frame, your options are limited to cards that are small enough or designed specially for the Mac Pro - that is, just any third-party graphics card is likely not to work with the system.

Obviously there's no room for other PCI Expansion slots or extra internal hard drives in the new Mac Pro. Instead, Apple has place a massive amount of faith in the new Thunderbolt 2 external expansion ports, of which there are an unprecedented six on the back of the new Mac Pro.

Apple's faith in Thunderbolt 2 expansion is understandable. Even compared to the first Thunderbolt, Thunderbolt 2 is an incredibly versatile and fast data-transfer system, providing double the bandwidth capability as the original (at 20 gigabytes per second) as well as combining the two previously 10 Gbps channels into one bi-directional 20 Gbps channel. That means daisy chaining up to 36 Thunderbolt devices, including multiple 4K video displays, external PCI expansion chassis, and super-fast external hard-drives where "backing up terabytes of data will be a question of minutes, not hours" according to Intel, Thunderbolt's designer.

So with the incredibly flexible and capable Thunderbolt 2, Apple is betting that all unforeseen upgrades and expansion can be done on the outside.

The only downside for power users is the cost of buying those extra externals, and the fact that the Mac Pro's tiny desktop footprint will quickly be traded away for a menagerie of wired devices all feeding into this tiny tin can.