A rule that declares not admissible as evidence any statement other than that by a witness while testifying at the hearing and offered into evidence to prove the truth of the matter stated. The reason for the hearsay rule is that the credibility of the witness is the key ingredient in weighting the truth of his statement; so when that statement is made out of court, without benefit of cross-examination and without the witness’s demeanor being subject to assessment by the trier of fact (judge or jury), there is generally no adequate basis for determining whether the out-of-court statement is true. The statements may be oral or written and includes non verbal conduct intended as a substitute for words.
If, for example a witness’s statement as to what he hears another person say is elicited to prove the truth of what that other person said it is hearsay; if however, it is elicited merely to show that the words were spoken, it is not hearsay. The witness’s answer will be admissible only to show that the other person spoke certain words and not to show the truth of what the other person said. There are many exceptions to the hearsay rule based on a combination of trustworthiness and necessity.