1. Explain the concept of redirection. Illustrate your answer with an example of a situation where redirection would be useful.
2. What purpose do arguments serve in a batch file or shell script?
3. Discuss the advantages that result from the client-server architecture of the X Window system.
4. The designers of the UNIX operating system describe the ideal shell command language as one that is made up of a large set of simple commands, each designed to perform one specialised task well. They also provided various means to combine these simple commands to form more powerful commands.

• What tools are provided to combine the commands?
• What are the advantages of this approach over providing a smaller set of much more powerful commands? What are the disadvantages?
• If you know something about the UNIX or Linux command set, discuss the characteristics of UNIX/Linux commands that make it easier to combine these commands powerfully?

5. Suppose that you are designing an app for a mobile device, such as iPhone or Android device. Name several services that you would expect to find in the operating system API to assist you with your program design.