What's the difference? Not a lot, really. In many cases, they are interchangeable, and you can use either 'speak' or 'talk' with exactly the same meaning. One of the few cases where you must use one but not the other is with languages. You would say 'I can speak English', but not 'I can talk English'. 'Speak' refers to one's ability to use language, whereas 'talk' means to converse. 'Speak' is often used more formal contexts. For example, you would say 'In Rome, the Pope came out onto the balcony and spoke to the people.' This is a formal situation, so it is appropriate to say 'speak'. 'Talk' might suggest a more informal conversation. Likewise, in a business context, you would probably ask 'Could I speak to Mr Black, please?' as this is more formal than 'talk'. There are also many set phrases, idioms and phrasal verbs where you need to use one but not the other, for example: Speak up! Speak your mind Speak the truth Talk nonsense Talk shop Talk down to someone Talk someone into something/ out of something I hope that helps.