An oldie but still good:

A professor explained about marketing to MBA students.

1. You see a gorgeous girl at a party, you go to her and say I am rich, marry me. That’s direct marketing.
2. You attend a party and your friend goes to the girl to tell her, he’s rich, marry him. That’s advertising.
3. The same girl at the party walks to you and says, you’re rich, do you want to marry me? That’s brand recognition.
4. You say I’m rich, marry me and she introduces you to her husband. That’s the demand and supply gap.
5.  Before you say I’m rich, marry me, your wife arrives. That’s restriction from entering a new market.