You use TELL when you are giving information or speaking directly with someone. It is always followed by a pronoun/person. ex: I told you to help her. I told Amy to come to the party. Ann told me the truth. Use SAY when you are merely expressing something or stating an opinion or fact. ex: I said I don't like orange juice. Mark says we should go to the movies. Ann says that apples are better than bananas. Hope that helps. :)

To tell means to say something to someone, often giving them information or instructions. Tell me about your italki experience, for example. Say means almost the same, to pronounce words or sounds, to express a thought, opinion, or suggestion, or to state a fact or instruction. She said good night to all her new italki friends and gone to bed as it was late.

Great answers here. For a super-short answer. Tell = SOMETHING to SOMEONE (ex. "TELL my boss I quit.) say = other (ex. "We SPOKE to the boss.")

I tell you this: /to say/ has usually an object like: word, sentence, sentences, a strong opinion, a belief. /to tell/ has usually an objetc like: a piece of information, a fact, a story, a narration.

I found this online: http://www.espressoenglish.net/difference-between-say-tell-and-speak/ I hope it helps.