(n.) Verification that something is correct or conforms to a certain standard. In data collection or data entry, it is the process of ensuring that the data that are entered fall within the accepted boundaries of the application collecting the data. For example, if a program is collecting last names to be entered in a database, the program validates that only letters are entered and not numbers; or in a survey collecting data in the form of “yes” or “no” questions, the program validates that only those responses are used and not some other word.
Validation procedures typically are written into the program code and are therefore invisible to the user.
