Lesson 1

Most of us manage our money by keeping a checking account. As we use the account, we keep a record of the transactions in the register. But how do we confirm that our records are accurate? We compare them against another record of the same transactions, a record that is maintained in a different place and in a different form than our own record.

Comparing and contrasting the two views make it possible to recognize discrepancies more easily. Once a discrepancy is found, it can be diagnosed and corrected. In addition, quite often the contrast itself will help reveal the cause of the discrepancy.
The correctness of the register contents cannot be verified using only the register. The same is true of diagrams.
One diagram by itself is very difficult to verify. But when different diagrams of the same problem are used together, then the process of comparing and contrasting the diagrams reveals potential problems.

This module covers a few ways to compare the different diagrams and provides some typical questions to pursue when you identify discrepancies.
In this module you will learn:

1. The importance of using different views to find discrepancies and opportunities for enhancement
2. How to test scenarios
3. How to test classes
4. How to test interfaces
5. How to recognize the patterns for reconciliation