Data validation is the process of ensuring that data entered into a system meets certain criteria, such as accuracy, completeness, and consistency. This can involve a variety of techniques, such as double-entry verification, range checks, format checks, and cross-field validation. The goal of data validation is to prevent errors or inconsistencies in data that could lead to incorrect conclusions or decisions. It is an important aspect of data quality management and is essential for maintaining the integrity and reliability of data used in analysis and decision-making.