"Heard" or "Heard of"

Hi,

Could you please tell me about the correct choice?

1- Have you----------of this idiom before?

(heard-heard of)

What are the differences between the two?

Thanks in advance

Tom

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Heard = directly perceived with your ears
Heard of = received brief information about
.

Thank you a lottttttttt, Mr. Micawber for all the support.

One more question: What should I say when talking to my friends? What sounds more suitable?

1- Have you heard this proverb? or
2- Have you heard of this proverb?

Tom

.
#1 is more suitable, Tom.
.