The Star Trek: Deep Space Nine: The Ferengi Rules of Acquisition

The Ferengi are greedy, avaricious, ruthless, cowardly and completely unscrupulous.
For centuries the famous Ferengi Rules of Acquisition have been the guiding principles of the galaxy's most successful entrepreneurs. These 285 Rules of Acquisition range from,

#1 "Once you have their money, never give it back."

to

#21 "Never place friendship before profit."

These rules and hundreds more have taken many successful Ferengi to new frontiers of profit.