Persuasion is the ability to convince others to do what you want them to do.
Nonplayer characters start at one of five different attitudes: Hostile, Uncooperative, Neutral, Friendly, or Helpful. A successful Persuasion roll improves the Extra's attitude one step, or two with a raise. Failure, on the other hand, decreases the character's attitude by a step, or two if a 1 is rolled on the Persuasion die (regardless of the Wild Die). Most Extras won't change their reaction more than one or two levels during a single exchange, but that's entirely up to the Game Master and the situation.
Charisma: Persuasion is always modified by a character's Charisma.
Player Characters: Persuasion should never be used on other player characters. Their attitudes should be decided entirely by their players.
Reaction Table: If the Game Master doesn't already have an initial attitude in mind for the Extra, he can roll on the chart below.
Savage Worlds Deluxe Edition p. 26