Unfamiliar with workflow? The below presentation could give you an introduction on What is a workflow, Why do we need workflow and how to create an application using the workflow.
For live demo on the same, go to the below link:
For those who are uncomfortable with designing workflow in workflow designer(.xaml file) and those who are good at C# and want to hard code without using activity APIs, Just add a class file with all the members as static and define a method and write your workflow. Now Come to your .xaml file in which drag and drop an invoke activity inside a sequence, browse your class name and type the method names given in the class file that you want to invoke. Build and Compile the code to get the desired result.