Credit cards are a valuable financial tool, provided you know how to use them. Unfortunately, a large number of Americans are in the dark about credit cards, and risk hurting their finances as a result. Nearly 50% of consumers say they've never received an education on credit cards, according to Credit Cards Explained. And that could shed light on why so many Americans are drowning in credit card debt. Whether you're applying for your first credit card at present or are simply intimidated by credit cards, here are a few important things you should know.

1. Credit cards can help you build credit

Credit cards tend to get a bad rap because they lead so many people into debt, thus wrecking their finances and damaging their credit scores. But if you use your card wisely, it can actually help you build credit. Of the various factors that determine your credit score, your payment history carries the greatest amount of weight.

Person handing another person a credit card

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Your payment history speaks to your tendency to pay bills on time, and it's a measure of how trustworthy and reliable a borrower you are. Therefore, if you consistently make charges on a credit card and pay your associated bills when you're supposed to, your score will start to climb.

2. Being late on your credit card payments can hurt your credit score -- and cost you money

Imagine you get your credit card bill, and it's much higher than what you can afford to pay at once. Your first inclination might be to put off that payment until you have the cash to cover it in full. Don't do that. If you don't at least make your minimum payment by its due date, you'll incur a late payment fee, not to mention start accruing interest on your total unpaid balance. Not only that, but you'll hurt your credit score once that late payment is added to your record. A single 30-day late payment could cause a strong credit score to drop 90 to 110 points, even if it's your first offense. Ouch.

A better bet? Always make your minimum payment on time. That amount is typically much lower than the total amount you owe, so you really have no excuse not to come up with it.

3. Charging too much on a credit card can hurt your score as well

Another factor that goes into calculating your credit score is your credit utilization ratio, which speaks to the amount of available credit you're using at once. To avoid having your score take a hit, you want that ratio to stay at or below 30%, which means that if you have a $10,000 credit limit, you should never owe more than $3,000 at a single point in time. Therefore, if you max out your credit cards even on occasion and don't pay them off right away, you'll risk not only racking up loads of interest, but sending your score into unfavorable territory.

4. Credit card fees aren't a given

Contrary to what you may have been led to believe, credit cards and fees don't automatically go hand in hand. This isn't to say that most cards don't come with fees, but rather, you can avoid most fees by choosing the right card and using it wisely.

One of the most common credit card fees you'll see is the annual fee, which is basically a sum you pay for the privilege of having a specific card. Under some circumstances, a card's annual fee might be justifiable given its benefits, but unless you have a compelling reason to want that card, like a stellar rewards program, you're better off opting for a no-fee card instead.

Then there's the aforementioned late payment fee, which you can steer clear of by simply being on time with your minimum payments. There's also the foreign transaction fee, which applies for purchases made overseas. Not every card imposes this fee, and if you open a travel card, you'll often avoid it. Furthermore, the good thing about credit card fees is that issuers are required to disclose them up front, which means that if you take the time to read the fine print on your credit card agreement, you can avoid losing money needlessly.

Though credit cards are a good way to build credit, protect your purchases, and collect rewards for the things you're already buying, you need to know how to use them. The more you read up on how credit cards work, the better positioned you'll be to make the most of yours without having it come back to bite you.