Defect density is a measure used in software development and quality assurance to quantify the number of defects or bugs in a given amount of code. It is typically calculated by dividing the total number of defects by the size of the software, often measured in lines of code or function points. This metric helps teams assess the quality of their software and identify areas that may need improvement. By analyzing defect density, organizations can track the effectiveness of their testing processes and development practices over time. A lower defect density indicates higher software quality, while a higher density may signal the need for more rigorous testing or code reviews. This metric is essential for maintaining the reliability of software products and ensuring customer satisfaction.