摘要：Software developers and maintainers need to read and understand source programs and other software artifacts. The increase in size and complexity of software drastically affects several quality attributes, especially understandability and maintainability. False interpretation often leads to ambiguities, misunderstanding and hence to faulty development results. Despite the fact that software understandability is vital and one of the most significant components of the software development process, it is poorly managed. This is mainly due to the lack of its proper management and control. The paper highlights the importance of understandability in general and as a factor of software testability. Two major contributions are made in the paper. A relation between testability factors and object oriented characteristics has been established as a first contribution. In second contribution, a model has been proposed for estimating understandability of object oriented software using design metrics. In addition, the proposed model has been validated using experimental try-out
