Update, 7/31/2018: Check out my new APR to APY calculator!
I am not one who can lecture you on the perils of credit cards from personal experience. I don’t have a redemption arc where I was once buried in credit card and student loan debt, but had an awakening and went on to dig myself out through sheer tenacity. I have 13 credit cards; buy everything using credit cards; got my first credit card at Age 19 (seven years ago); have received tens of thousands of dollars in credit card signing bonuses, cashback, and rewards such as Chase Ultimate Reward points, American Express Membership Reward points, Southwest Airlines Rapid Reward points, and Starwood Hotels Preferred Guest points; have never paid a cent in interest; and pay in full (PIF) every month by the due date (except during the occasional 0.00% APR introductory period).
I have not studied business or finance formally—I went to college for a Bachelor’s in psychology and a Master’s in applied learning and instruction. However, I have been interested in personal finance since I was a teenager in high school and read extensively via Internet searches before receiving my first credit card (a Discover More card, now called Discover It). I heard and internalized the horror stories about penalty interest rates, drowning in debt, bankruptcy, collections, et cetera. I avoided and continue to avoid consumer debt traps, aided by never moving out of my parents’ house, living in Florida where in-state tuition is cheap, having low-income parents which enabled me to receive the maximum Pell grant during my undergraduate studies, and probably a genetic or acquired lack of susceptibility to the lure of over-spending with credit cards.