What is Thunderbolt? Here’s everything you need to know

Thunderbolt 3 vs. USB-C: How to make sense of your laptop's port options

Computer peripheral cables are hard enough to keep track of without people throwing around words like “Thunderbolt” and “Type C.” Thunderbolt may be particularly confusing, since this connection technology has gone through several different phases, and is making the jump from Apple to laptops and PCs in general.

But knowing the difference between these different ports is important, especially when you’re thinking about which computer is right for you. These days, don’t be surprised if you look at a new laptop and see nothing but “USB-C” and “Thunderbolt.”

So, what exactly is it? Let’s take a look.

The Thunderbolt 3 of today

Bill Roberson/Digital Trends
Bill Roberson/Digital Trends

Thunderbolt technology has been around for since the late 2000s, but by the time Thunderbolt 3 had shown up in 2016, times had changed. Specifically, USB-C had emerged as the latest USB standard, an updated and powerful USB cable that could provide up to 15 watts of power for devices (far more than older standards) and up to 100 watts for charging compatible laptops or similar devices. It was a sea change for USB, and clearly the future of many common computer connections.

In response, Thunderbolt’s developers made a very smart decision: Rather than try to face off against USB-C, they joined it. Thunderbolt 3 ditched the old DisplayPort connection base, and switched to a USB-C connection, basically combining the two technologies into one particularly powerful hybrid.

The move to USB-C allowed the Thunderbolt 3 to make the leap from Apple devices to other PCs and laptops, a process that is ongoing but finally possible. The only downside was the issue of compatibility — the new USB connection isn’t compatible with Thunderbolt or Thunderbolt 2 without a pricey adapter.

Here are some things you can do with a USB-C Thunderbolt 3 port today:

  • transmit data at a rate of 40 Gbps
  • output video to two 4K monitors at 60 Hz
  • charge smartphones and most laptops with up to 100 watts of power
  • connect to an external GPU (unless it’s been blocked by the manufacturer)

If you’re wondering whether or not your USB-C port is actually Thunderbolt 3, look for that little Thunderbolt symbol nearby, which often differentiates it from a standard USB-C port.

The history of Thunderbolt technology

Thunderbolt technology originally began in the late 2000s as an Intel project called Light Peak, which was intended to add optical data transfer to traditional data transfer used with computer peripherals (essentially, combining wire and fiber optics). However, they soon found that their prototypes with good old copper wiring were already achieving the results Intel wanted, at a much a lower cost.

This new product was then released as Thunderbolt in the early 2010s, at first available only on Apple devices: It was designed to be a particularly powerful and flexible connection. Compared to the (often brand-specific) cables floating around in those days, this was an impressive creation suitable for many purposes. It was particularly promising for designers or engineers who were using laptops but still needed high-powered connections to external storage, high-resolution displays, and similar accessories.

However, technology continued to march on, and before long there was a Thunderbolt 2, and a Thunderbolt 3.

Because the first Thunderbolt release made it out the door with some help from Apple, it was only available for Macs for the first year or so. Intel wanted to bring the connection to PCs, but for now it decided to stick with Apple exclusivity. In addition to limited availability, the other downside to this new tech was the unique Thunderbolt cables were required, and they tended to be expensive — around $50 or so.

Dan Baker/Digital Trends

Thunderbolt 2 made several major changes to Thunderbolt technology around 2014. Namely, time had provided a more accurate look at how Thunderbolt was being used — and where it should head in the future.

The result was a new type of cable that combined the two 10 Gbps bi-directional channels of the first cable, and created a single 20 GBps bi-directional channel that could provide more oomph to peripherals when necessary. These cables quickly showed higher speeds than any other popular peripheral cable of the day. Compatibility with the latest DisplayPort standards came with Thunderbolt 2 as well, since the two technologies still needed to work together.

One of the most important changes, however, was 4K compatibility. While still a little ahead of its time, 4K resolution was on the horizon, and users who depended on Thunderbolt connections were glad to know that the highest resolutions would be supported when necessary. Also important for users, Thunderbolt 2 devices were backwards compatible with the original Thunderbolt-compatible devices, even if you wanted to mix and match different generations. Again, the Thunderbolt would stay exclusive to Apple computers until the move to USB-C with Thunderbolt 3.

The latest Thunderbolt developments

Bill Roberson/Digital Trends

Updates to Thunderbolt continue, as do the growing ways that Thunderbolt is being used in devices. Charging devices using USB-C Thunderbolt connections has become more common, and compatibility has pressed onward to include the latest USB 3.1 cable standard (although this is still a work in progress, so always double-check your cables).

New challenges are also growing for Thunderbolt, as impressive as the connection remains. For example, the USB4 standard is on its way, and it finally promises speeds that can rival Thunderbolt 3. According to official data, USB4 will offer two-lane data transfer with total speeds up to 40Gbps. While Thunderbolt is more than just high-speed data, this will put more pressure on the Thunderbolt standard to continue its evolution.

There are also security threats to consider. The Thunderclap vulnerability was recently reported to be present on Macs and PCs: It allowed hackers to use the Thunderbolt port, via a device loaded with the right malware, to access and steal files on the computer by bypassing Thunderbolt security measures in seconds. It’s an important reminder that these high-speed connections come with their own risks, and should never be used with unfamiliar devices.

Computing

Here's our guide to how to charge your laptop using a USB-C cable

Charging via USB-C is a great way to power up your laptop. It only takes one cable and you can use the same one for data as well as power -- perfect for new devices with limited port options.
Computing

Dodge the biggest laptop-buying mistakes with these handy tips and tricks

Buying a new laptop is exciting, but you need to watch your footing. There are a number of pitfalls you need to avoid and we're here to help. Check out these top-10 laptop buying mistakes and how to avoid them.
Computing

In 2019, laptops are better than ever. Here are the best of the best

The best laptop should be one that checks all the boxes: Great battery life, beautiful design, and top-notch performance. Our picks for the best laptops you can buy do all that — and throw in some extra features while they're at it.
Computing

If you can only buy one, should it be the MacBook Pro or the iPad Pro?

If you need a powerful, portable device that can handle any task you throw at it, both the MacBook Pro and iPad Pro fit the bill. But which one is best? We run down the pros and cons of each device to help you decide which one you should…
Computing

Keep your laptop battery in tip-top condition with these handy tips

Learn how to care for your laptop's battery, how it works, and what you can do to make sure yours last for years and retains its charge. Check out our handy guide for valuable tips, no matter what type of laptop you have.
Deals

Now’s your chance to get the latest iPad Pro for $100 less on Amazon

The latest iPad Pro has always been our favorite since its release last year, and we even tagged it as the best tablet ever. Don’t miss out on Amazon’s discount on the 12-inch 256GB Wi-Fi model and get yours today for $1,049.
Computing

1.5% of Chrome users’ passwords are known to be compromised, according to Google

In February, a new feature was introduced to the Google Chrome browser which checks whether users' passwords are secure. Now, Google has released eye-opening stats gathered from Password Checkup.
Computing

From Chromebooks to MacBooks, here are the best laptop deals for August 2019

Whether you need a new laptop for school or work, we have you covered. We've put together a list of the best laptop deals going right now, from discounted MacBooks to on-the-go gaming PCs.
Deals

Amazon cuts $52 off this Samsung Galaxy 10.1-inch tablet for the whole family

Normally priced at $330, you can grab the Samsung Galaxy Tab A 10.1-inch 128GB Wi-Fi tablet now for only $278 and enjoy $52 savings. On top of that, Amazon is offering an extra $28 discount when you apply for a coupon during checkout.
Computing

Tired of choosing between Windows and Mac? Check out these Chromebooks instead

We've compiled a list of the best Chromebooks -- laptops that combine great battery life, comfortable keyboards, and the performance it takes to run Google's lightweight Chrome OS. From Samsung to Acer, these are the Chromebooks that really…
Computing

Tired of your Mac freezing? Try these tips to fix your Mac

A Mac that keeps freezing can be an incredibly annoying thing to deal with, but fixing it doesn’t have to be a pain. There are six main things you should try, which we got through in this guide to help you fix the issue once and for all.
Computing

Latest Windows 10 update is causing random reboots and can break Visual Basic

The latest update for Windows 10, made available on Tuesday this week, includes patches against two critical vulnerabilities. But it is causing a string of issues including random reboots and failure to install.
Computing

Delete tracking cookies from your system by following these quick steps

Cookies are useful when it comes to saving your login credentials, but they can also be used by advertisers to track your browsing habits across multiple sites. Here's how to clear cookies in the major browsers.
Computing

Enjoy your music on more devices: Here's how to convert FLAC to MP3

FLAC files sound awesome — that is, if your device can handle the lossless format. No matter your OS there's a converter for you. Here's how to convert FLAC to MP3, so you no longer have to worry about incompatibility issues.