These are generally used in terms of finance, our money. A debit is an amount of money subtracted from what we have. A credit is an amount of money added to what we have.
For instance, if I have $200 in the bank and make a $50 deposit, the bank with credit my account with $50, giving me a new total of $250.
If I have $200 in the bank and write a check for $50, the bank will debit my account for $50, meaning the bank will take $50 out of my account, leaving me with a new total of $150.
Simply put, debit means to "take away" and credit means to "add to." So, when it comes to money, credits are better than debits!