It’s well known that carrying too much credit card debt or missing credit card payments will hurt one’s credit score. Few people, however, are aware that credit cards also can be a great way to begin to build a credit history.

Credit scores have always been important, but today, more than ever, your credit scores rule your financial destiny. With tightened lending practices and stricter underwriting rules, paying attention to your credit score is no longer simply a choice, it’s a necessity.

What a difference a few hundred years make. Like our forebears of yesteryear, we hold certain truths to be self-evident: that we’re all endowed with certain unalienable rights and that all men (and women) are created equal—as long as our credit score meets a certain minimum benchmark.

Having bad credit can be costly. Not only does bad credit make it harder to get approved for mortgages, auto loans, or a new credit card; if you do get approved, the loan will come with more restrictive terms and higher interest rates.

The world of credit is changing fast, and so are the benchmarks for what is considered good credit. In today’s tightening credit environment, people who once had good credit may find that their score no longer measures up.