Here's what you need to know before you shop for a new TV on Black Friday

Black Friday is a popular time to buy TVs, but it can also be intimidating if you don't know what you need.

There are so many TV specifications that shopping for one can be overwhelming and confusing. It's like an acronym assault. What is HDR? What does 8K mean? What's the difference between LCD, OLED and QLED displays? How important is the brand?

The discounted TVs on Black Friday may not be the best of the best. "TVs you'll find on Black Friday are typically going to be entry-level sets," said Paul Gagnon, vice president and industry advisor for the market research company The NPD Group. Gagnon, who has been covering the TV industry for 25 years, said it's especially important when a TV is discounted that you make sure it has all the features you need before you buy it.

Here's a guide to explain all those important features so you can find the TV that's best for you.

4K TVs are the standard these days. If you're not sure what 4K means, it describes the picture resolution. TVs with 4K have four times as many pixels as standard 1080p resolution sets. But keep in mind most live broadcasts still aren't shot in 4K, so you'll mainly see the benefit in apps such as Netflix and Amazon Prime Video, or if you subscribe to YouTube TV with the 4K premium bundle.

When choosing between resolutions, you might see specifications such as Ultra HD, UHD, or 4K. They all mean the same thing.

8K resolution has double the resolution of 4K. It amounts to four times the pixel count of 4K and 16 times more pixels as 1080p.

While that might sound enticing, you probably won't enjoy any of the benefits of 8K since there isn't any content shot in 8K yet. Not to mention 8K TVs are pricey. Be prepared to spend over $2,000.

HDR, otherwise known as high-dynamic range, allows your TV shows and movies to look as intended by the studio that produced them if they're shot in HDR. You'll get more light in darker scenes, meaning it's easier to see the content. Most 4K TVs have HDR compatibility too.

There's a wide range in the quality of HDR TVs. Expensive ones can look great, while cheap ones may not. If it's done right, HDR can actually be a more important feature than 4K.

Good HDR comes down to brightness and contrast. When the light parts of the TV image are brighter it improves the color and makes the picture look like it has more depth and the movies and TV shows can look more lifelike. Let's say you're looking at a movie with a shot of the ocean, you'll be able to see the nuances and textures of the wave, the deepest blues and the white caps, making you feel the realism of the scene.

But HDR performance can vary drastically from TV to TV. Make sure the TV you buying has a brightness of at least 400 nits — a measure of the intensity of brightness — since sometimes TVs with levels lower than 400 get marketed as HDR TVs, too. 600 nits or brighter is better, with the best-performing HDR TVs hitting 1,000 nits or more.

You'll see a lot of different types of HDR marketing. HDR10 is most widely used because it's an open and free technology standard. Pretty much all TV sets marketing HDR support will work with HDR10 content.

There's also HDR10+ which is supported by most of the major streamers, except for Netflix. Keep in mind though, TVs can receive updates, so if a manufacturer decides to hop on board with HDR10+, the company can add that capability to your TV without you needing to do anything but update the software.

A TV's refresh rate is the number of times per second it can reset and display an image. Most TVs today offer either 60 Hz, meaning the display refreshes 60 times per second, or 120 Hz, refreshing 120 times per second.

The latter is more expensive but can be better if you watch lots of fast-moving content, like sports or action movies. When refresh rates are low, it creates motion blur, which makes a moving picture look fuzzy.

This number is especially important for gamers. The latest consoles, such as PlayStation 5 and Xbox Series X, offer 120 Hz refresh rates, but you'll need a true 120 Hz TV in order to see graphics as clearly as possible.

If you're hooking up a gaming system that uses a higher refresh rate, "make sure the TV has an HDMI 2.1 input," Gagnon said. That's the port that will support these fast refresh rates, he said.

Almost every TV today uses either a liquid crystal display, known as LCD, or an organic light-emitting diode screen, known as OLED. The latter is capable of producing the best picture quality, while LCDs generally cost less but can still give you a great picture.

OLED is a newer technology. It doesn't have a standard backlight. Instead, each pixel is illuminated on its own. The best quality LCDs, on the other hand, have local dimming, meaning parts of the screen can get dim without impacting the brightness on the rest of the screen.

"LCD's biggest advantage is that it's by far the most affordable of all of the technologies," said Gagnon. "The very high-end LCD TVs do a pretty good job of coming close or matching the performance of OLED displays."

With OLED, "then you're talking about typically what is the highest performance display, so it's going to have higher contrast levels, and better color performance." It will also be easier to watch the TV from multiple viewing angles, and it will probably have the fastest refresh rate, Gagnon explained.

There's also QLED, which stands for quantum light-emitting diode. A QLED TV is essentially an LCD TV with quantum dots. Quantum dots are tiny molecules that, when hit by light, emit their own differently colored light. Because of this technology, QLED TVs more accurately emit colors, which improves the overall picture quality.

With QLED, "you get better color performance, you also get a little bit of an efficiency improvement, meaning the set can be a little bit brighter, and oftentimes these tend to be TVs that include other features, for example, higher refresh rates and more HDMI inputs," Gagnon said.

Almost all TVs are smart now, so no matter what brand you choose, you'll probably have apps that come preloaded on your new TV. You can connect an external streaming device to any TV, such as an Amazon Fire TV Stick, a Roku box or an Apple TV. If you do, go for one that features 4K and HDR, as long as that's what your new TV supports. That way you'll ensure you have the best viewing experience possible.

When it comes to using the preloaded apps on your TV, it's important to know that smart TV stores, where you can download apps for your TV, vary depending on the TV's brand. Samsung TVs will let you access the Samsung Smart TV store, and LG TVs have the LG Content Store. Other brands, including TCL, Hisense, and Toshiba, partner up with streamers you're familiar with, such as Roku, Google and Amazon.

It's less important to find the TV that has the smart service you like built in and more important to find the best quality TV. You'll always have the option to add a streaming device externally to the TV if you favor one company over another.

If you're relying on the TV's built-in applications, Gagnon suggested, make sure the smart TV you're buying supports all the streaming apps you frequently use. And if you have an iPhone and like to mirror the screen, make sure your TV supports Apple's screen mirroring. If you're an Android user, make sure your TV supports casting, Google's version of sharing content from a phone to a TV.

Since TVs are so thin these days, there isn't a lot of room for speakers, which means most TVs have pretty poor sound quality. Sound bars can solve this issue by providing larger speakers with deeper bass and better range. They'll help a bit if you've ever run into an issue where a TV show is super quiet in some scenes and then really loud in others. You can find good ones for a range of prices, anywhere from $100 to $800. You may even score a free one on Black Friday if a retailer bundles them with a TV purchase.

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