Chapter 1 to 4 shows most of the useful and important shell scripting concepts. Chapter 5 introduction to tools & utilities which can be used while programming the Linux shell smartly. Chapter 6 and 7 is all about expression and expression mostly used by tools such as sed and awk. Chapter 8 is loaded with tons of shell scripting examples divided into different categories. Chapter 9 gives more resources information which can be used while learning the shell scripting like information on Linux file system, common Linux command reference and other resources.