Q2) Version control products (SourceSafe, PVCS, etc) allow you to save your source code in such a way that prior version of your source can be recovered. They allow you to compare differences from one version to another. They allow you to merge changes to one class by multiple programmers so that no changes are lost. They prevent one programmer from working on source when another programmer is working on that source. In a multi-programmer environment, version control can be critical to a project. Here is a FAQ from SourceSafe: http://msdn.microsoft.com/ssafe/Prodinfo/qa.asp Q3) JDBC 20? Ask again in about 15 years or so.