Fun Facts About Credit Cards: Our Intro to Credit Card Basics

We review the fundamentals of credit cards and also cover some fun facts about credit cards along the way. Great for beginners!

Updated April 2024

Fact checked by Cathy Gresham

Credit card basics

Starting thoughts

It’s a constant shock to find out how many people don’t understand the fundamentals of credit cards basics, despite having several cards. Most Americans have and use credit cards, but I am constantly shocked at how many people either misuse or misunderstand cards. Americans now owe more than 1 TRILLION dollars in credit card debt!

This article will review some credit card basics, what they are, and how you should use them. This is a foundational article in a series of articles about credit cards. If you’re a more advanced reader – feel free to skip ahead to those!

Along the way, we’ve also provided some fun facts about credit cards, which should also give you a sense of some of the basics of what’s going on with this product.

Fun Facts About Credit Cards #1

Credit card fact #2

What is a credit card fundamentally?

A credit card is just one type of unsecured revolving credit, which is a form of debt. What this means is that a financial institution extends you a line of credit of some amount that can be repaid by you at any time. Unlike in a traditional, simple loan, there’s no set repayment schedule, although likely minimum monthly payments are depending on how much of the line of credit you have utilized.

This has the advantage that you can pay back on your schedule, rather than per a fixed repayment schedule. This feature can also be what tends to get people into trouble, though, as they let debt on the card continue to accrue interest. This gets doubly bad when you factor in the high-interest rates cards typically carry. Credit card companies charge these high rates for 3 main reasons:

  1. Unsecured debt – they have no collateral to immediately seize if you don’t pay your bill
  2. The debt is almost always used to purchase a good or service which does not increase the debtors’ ability to repay (e.g. used for clothing instead of a business expense which might make more money in turn)
  3. Adverse selection problem – debtors with a strong ability to repay often have better/cheaper options than using a credit card

Credit cards have evolved to become an everyday fact, something you probably use multiple times per day and in nearly every commercial transaction you make, but they are at their core, simply unsecured revolving debt

Fun Facts About Credit Cards #2

Credit Card Fun Fact #2

The credit card companies’ perspective

Credit cards are an incredibly profitable business. This is why you might see cards offered from companies that you don’t think of as credit card companies, like airlines, furniture stores, and sports teams.

Credit card companies make their money in two ways

  1.  Interchange fees – this is the money the merchant pays to the credit card companies when you swipe your card at their store. Of course, merchants build this fee into their prices, so really it’s still you who is paying. This fee varies by company and can even be individually negotiated with large merchants, but typically ranges around 1-2% of the transaction plus $0.25
  2. Revolver fees – this is the money the card money makes from debt that has not been repaid on time and accrues interest.

While interchange fees are an important source of revenue, credit card companies make the vast majority of their money from revolver fees. That’s kind of the opposite of a fun facts about credit cards. Yikes. 

This is why they hope you forget to pay your balance each money and carry it over to the next period, where they start charging you interest. This might be why you see them make their websites and bills and terminology so confusing – it’s all to hope you don’t pay that bill on time before it starts accruing interest. And they can make a lot of money doing this since most people don’t understand these credit card basics.

Fun Facts About Credit Cards #3

Credit Card Fun Fact #3

Reasons not to use a Credit Card

If you’re unable to use a card responsibly and pay it off each month, you should stop reading now and not use credit cards! Maybe just stick to reading the graphics about the fun facts about credit cards instead!

The interest rate charged will likely be 15-25%, if you don’t pay in full each month, which is essentially punitive. Especially if you are low-income and/or tight on money, increasing your monthly expenses by 15-25% can cause your personal finances to spiral out of control.

Another, sneakier, reason not to use credit cards is the way credit card companies calculate how much interest you owe if you don’t pay your full balance on time. You might reasonably think that if your statement closes on the 1st of the month and the bill is not due until the 21st of the month if you’re late by a couple of days it’s no big deal after all 15-25% annual interest multiplied by a couple of days should end up being a pretty trivial amount. Maybe just a couple of dollars, depending on how much you spent.

But this doesn’t account for the sneaky way credit card companies set up their billing cycle. How it actually works is that your bill is due when it closes on the 1st and the time they give you to pay until the 21st is the ‘grace period.’ You might not realize this since most companies’ bills/websites make it look like your bill is not due until the end of the grace period.

So if you don’t pay by the 21st the companies charge you interest back when you incurred the charge. So if you incurred your charges on the 21st of the previous month, by being 1 day late after the grace period, they will charge you a full month’s interest!

Fun Facts About Credit Cards #4

Credit Card Fun Fact #4

Reasons you should use Credit Cards

If you are responsible, understand credit card basics, and will pay off your credit cards in full monthly except in rare circumstances there are two main reasons you should have at least one card (if not more)

As mentioned earlier credit card companies charge their merchants an interchange fee, so merchants build this cost into their prices. These days, with the high prevalence of credit cards, most merchants simply set prices assuming most people will use their credit cards. And, with rare exceptions, they tend to set one price that everyone pays regardless of the method of payment.

But if you use a credit card, you will tend to get most of that interchange fee back in the form of credit card rewards (which take many forms and will be a separate article). Depending on how you use your card, and which card you have, you may even recapture more than what the interchange fee was

The more popular and well-known reason to have a credit card(s) is to build credit. By having a revolving credit line open and paid in full each month, you will help to build your credit score, which could help you get more favorable terms on other types of debt like a mortgage. Obviously, there is a lot that goes into this, so it too will be a whole separate article.

Fun Facts About Credit Cards #5

Credit Card Fun Fact #5

How to use Credit Cards

There are two main things to remember to responsibly use credit cards:

  1. Pay them off in full every month. This will help you avoid a personal finance spiral where you’re paying punitive rates like 15-25% annually. Of course, there could be certain rare cases or emergencies where it makes sense to carry a balance and suck it up and pay the interest rate, but these should be exceedingly few and far between
  2. Don’t wait until the end of the grace period (many will list that as your due date, instead set a reminder to pay as soon as the bill hits). As described above, missing the bill payment due date can easily and quickly lead to a month or more’s worth of interest charges. Instead of setting reminders to pay your bill at the end of the grace period, set them to pay it as soon as the statement is issued. This way if you forget or get busy and miss by a couple of days, you still will not have accrued any interest. It varies, but most cards’ grace period is about 3 weeks

Are you interested in other credit cards? 

Check out our credit card hub!:

  • Personal Finance Guru Credit Card Hub

My top credit cards and credit cards to avoid

My favorite cards come from USAA, Fidelity, and Chase. USAA offers a 2.5% flat cashback on all charges cards – the highest I’ve ever seen. Fidelity has 2% flat cashback that goes straight to your investment account – another great feature combo. And finally, if you’re willing to deal with a little less flexibility, Chase offers a very high redemption rate if you redeem their rewards through their travel rewards portal – worth it if you spend enough and care about travel.

I don’t recommend American Express, after too many negative customer support experiences, I no longer do business with them.

Wrapping up

Hopefully, you now understand most credit card basics and are ready to start using them responsibly for some great benefits. Credit cards can be a great tool to earn rewards like cash back or flights or hotels and to build credit. They can also be a backup to pay for unexpected expenses  But like any tool, if used improperly they can be dangerous. For most responsible people I recommend having a few!

Now that we've covered the basics and fun facts about credit cards, check out some of our top content:


Editor's Note:

At Personal Finance Guru, we want to help you maximize your lifestyle through personal finance. You can trust the integrity of our independent financial advice. Our opinions are our own and have not been provided, reviewed, approved, or endorsed by any advertiser or financial product provider. To support and grow the site, however, we may receive compensation from the issuers of some products.

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Cody Beecham

Cody Beecham


Cody is the founder and owner of Personal Finance Guru. His day job is as a management consultant at one of the Top 3 firms (think Mckinsey, Bain), where he advises Fortune 500 C-suite clients on their most important and pressing business problems. He completed his business education at Harvard Business School. 

After seeing the lack of personal finance education for regular people, Cody started the website with the mission to provide everyone access to information that will help them achieve their financial goals.

Cody approaches personal finance from a maximalist perspective, shunning typical advice around simply not buying a cup of coffee instead of more effective methods like investing in yourself to quickly grow your income. 

He believes in saving money and investing for the future, but he also knows that you need to enjoy life today. That’s why Cody approaches money with a sense of humor and a positive attitude. He knows that if you’re not having fun while you’re growing your wealth, then what’s the point?

Cody approaches life with the same gusto that he brings to personal finance. He loves to travel and experience new cultures, and he is an avid reader and learner. He also enjoys playing sports (especially tennis) and spending time with his family and friends.