Speech

The Speech skill affects dialogue. Certain characters will have a speech option available when talking to them. Succeeding in a speech option can earn you things such as extra caps, discounts when buying or information for a quest, and new opportunities. Each speech option will have a percentage next to it telling you the chance (out of 100%) you have of succeeding, if you fail a speech option it's removed from the dialogue options and usually can't be asked again. Your Speech level will increase depending on your Charisma, each Charisma level will increase your Speech by +2.

[edit] Increasing Speech skill

• Speech Bobblehead - Speech +10
• Impartial Mediation Perk - Speech +30 (only if you have Neutral Karma)
• Scoundrel Perk - +5 Speech
• Lying, Congressional Style - Each book increases Speech by +1 (+2 if you have the Comprehension perk)