Black Friday is one of the biggest retail shopping days in the U.S., and this year 115 million people will brave crowds on that day in search of the best deals. The National Retail Federation (NRF) says that the average shopper plans to spend about $967 over the holidays, up from $935 last year -- and each one of those shoppers wants that money to go as far as possible, of course.

Many consumers can't help but be enticed by the seemingly endless number of deals during the holiday season, but there are a few things that retailers would prefer the shopping public doesn't know about their too-good-to-be true deals.

Image of 50% sale sign in retail window.

Image source: Getty Images.

1. Black Friday may not be the best day to shop

Gasp! I know, this is a shocker. Sure, there are amazing doorbuster deals that you probably won't find any other time of the year on a select few items, but Black Friday isn't the best day to shop for everything.

For example, you can usually find the best deals on toys closer to Christmas, according to NerdWallet. And while you can certainly find great deals on TVs during Black Friday, you can also find similar television deals just before the Super Bowl. 

Also, it may be best to stay away from things like jewelry during the holidays, if you want to save the most money. Lots of people are buying jewelry right now, so there's little incentive for companies to make steep discounts. Instead, wait until the Spring -- and after Valentine's Day -- when people are less likely to be buying something special for their significant other. 

2. There's a very limited supply of doorbuster items

The big-ticket items that are drastically marked down -- or at least seemingly so -- are the ones that lure shoppers into stores. And while these deals can be good, there's often a very limited number of them available. Many of the doorbuster deals you see in the Black Friday ad papers and online will say things like "limited quantity" or "no rain checks" in the fine print, and some will even tell you the number of items that'll be available in each store (hint: it's not many).

Many times these deals are meant to get you into the stores with the hope that once you're there you'll spend oodles of money on other items -- even if you don't get the doorbuster deal you initially came for.

3. Some discounts only seem like good deals 

You might think that you can outsmart the retailers by scouring all of the ads and comparing prices, but that's not always possible. That's because many retailers sell very similar products (like TVs) with completely different product numbers. This makes it difficult to know whether or not you're getting the best deal.

A recent Consumer Reports shopping guide said, "For instance, large retailers might apply their deepest discounts to TVs with a specific model number, which makes it difficult to be sure you're doing an apples-to-apples comparison. In some cases, comparison shopping isn't even possible."

That doesn't mean you shouldn't be on the lookout for a good deal, but it could be hard to figure out how deep the product discount is if you don't have a comparable product to match it up with. 

4. Not all products are created equal

Last, but certainly not least, you'll need to be on the lookout for products that are made specifically for Black Friday and the holiday shopping season. This can happen with certain electronics -- and the best example is, again, TVs. Some of these products are created with a limited supply, don't have any price history, and are sparse on the specification details. Sometimes they'll be manufactured with less-than-stellar parts, and because they're so new you're unlikely to find any product reviews.

All of this can make them less of a great deal. So before you buy anything on Black Friday, and particularly if you're shopping for TVs, find out as many specifications of the device as possible and try to find a similar product to compare it to before you buy.

One last shopping secret

Before you head out to brave the holiday crowds ,it's worth mentioning just one more important thing retailers may not want you to know: The more you chase sales, the more likely you are to overspend. A report by the Center for the New Middle Class showed that shoppers who hunted down good deals were 45% more likely to report that they overshot their holiday shopping budget. Remember that all of the Black Friday deals are designed to entice you to spend more money, so don't get sucked into the hype.

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