Any document or a paper which is presented and allowed by the court in the hearing, trial or a plea as evidence, as distinguished from oral testimony. And the opposing attorney (defendant) main object to date one has been admitted. Firstly it must be proved by another witness from the help of evidence that this paper is genuine or not, this process is called laying a foundation, in other words, we can say that this evidence may be found in oral either in written form. The availability of that document is based on the authenticity of the documents and also that purpose for which it would be used in court of law as evidence. There are a few ways present through which we challenge this evidence. (i) Parol evidence (ii) authentication (iii) best evidence (iv) hearsay. There are also several documents present which are always self-authenticated by Federal rules of evidence (FRE). These are