Validation or data validation is the checking or verification of any data that comes into the computer, which helps verify the data has not been compromised or corrupted during transmission.
Performing data validation is important to ensure that incoming data is accurate, complete, and it has not been corrupted in any way. Corrupted data can result in the inability to view or process the data, which can mean the data would be lost. Incorrect or incomplete data could result in a flawed or invalid analysis of the data.
For example, if a bank receives a file with bank account data for 100 clients, the bank will validate the data is accurate, all data is included in the file, and the file is not corrupt. The validation ensures the bank is receiving all data and can load it into their computer systems. If the bank did not validate the data, and the data was inaccurate, incomplete, or the file was corrupted, not all data would be loaded into their computer systems. That would result in lost data and clients could lose money in their bank accounts, which would make them very unhappy.