For software publishers, a less expensive method of copy protection is to write the software so that it requires some evidence from the user that they have actually purchased the software, usually by asking a question that only a user with a software manual could answer (for example, "What is the 4th word on the 6th line of page 37?"). However, this approach can be exploited with the patience to copy the manual with a photocopier, and it also suffers from the issue of making the product more inconvenient for the end user to use.