Time sheets are collected in a batch, and the information is manually keyed into the system. This data is now stored on a magnetic disk. An editing program is run, which verifies whether the employee number is valid by checking it against an employee master file. The validity of the cost center assigned is also verified against a master file. Logical and clerical errors should also be tested, such as an employee working an unreasonable number of hours in a day/week. Records that are found to be in error are sent to an error file. These errors need to be investigated and corrected. The good records are stored in a data file. The next program takes the edited transaction records, one at a time, and updates any corresponding fields in the master files. Finally, a report program generates paychecks and management reports.