mand. Web based software products involve creating user interfaces, creating business lo-
gic and using a database to store permanent data.
When programmers write code, the code may contain some kind of error like syntax error
or control flow error etc. When these errors are there in the code and the programmer tries
to save (compile) it then the compiler will raise errors. To find these errors and fix them is
known as debugging. There are good automated tools known as debuggers. These debug-
gers are provided in IDEs.
Software projects which have an agile methodology, build software products incrementally.
New product features are built on top of existing product. When the product size becomes
large then previously written source code makes it difficult to write new source code be-
cause of many reasons like program element names no longer relevant or some source code
needs to be placed at some other place as it becomes more relevant there. For doing these
design changes, programmers make changes in the existing source code. This activity is
known as refactoring.