Which data anonymization technique involves replacing sensitive data with artificial values?

The data anonymization technique that involves replacing sensitive data with artificial values is 'data masking' (also sometimes referred to as 'data substitution'). Data masking replaces real data with realistic, but fabricated data, so the format remains consistent, but the original sensitive information is concealed. For example, a phone number could be replaced with a different, but valid-looking, phone number; or a name could be replaced with a randomly generated name. This allows for testing, training, or analysis to be performed on a dataset without exposing the actual sensitive information.