For example, proof of mailing a letter is prima facie proof that it was delivered to the person to whom it was addressed and will accepted as such by a court unless proven otherwise.
Other situations may require a prima facie case before proceeding to another step in the judicial process.
The rules of court and of procedure often allow that photocopies of business record or mgovernment documents constitute prima facie proof of their authenticity which sets down a presumption that they are as good as the originals subject to evidence to the contrary.
The signatures of officials and officers are also often taken as prima facie evidence as this sample from the US Code, Title 33, Chapter 17.1, ¶876:
"The signature without seal together with indication of grade of any officer performing any notarial act shall be prima facie evidence of his authority."