One card you may want to also consider is American Express. While it's accepted in fewer places than a Visa or Mastercard the regular card's balance must be paid for in full each month, unless you take the Sign and Travel option, in which case certain purchases (such as plane tickets, hotels and car rentals) can be paid off over time. Don't get the Optima or Blue card if you intend to pay your balance in full; they're revolving charge accounts.
Basic card's the green card, you become eligible for Gold if you spend more than $5000 in a year or have five years of credit experience ('cardmembership'). Then it's an additional $85 a year for Gold. For those with bigger bank accounts, for $300 a year you can get the Platinum card (with at least five years as a Gold card holder), with bigger bennies (automatic entry to most major airline clubs on the day of travel is but one of 'em). The best of the best customers in the Amex pecking order get the black Centurion card; that's extended only to Platinums with impeccable credit and by invitation only. (Amex created the Centurion card to distinguish it from the devalued Platinum; every Visa, MasterCard and even Discover card issuer issues platinum or titanium cards, even Plutonium if they could get away with it.
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Be wise handling your credit; it isn't an instant cash machine when you need cash and your checking account is near zero (cash advances are killers in interest).
Citibank has similar cards; Diners Club and Carte Blanche, don't get those unless you do strictly travel and entertainment expenses as they're accepted in even fewer establishments than Amex.