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 title: Effective Shell
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+sidebar_label: Introduction
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 import { EmailSignupForm } from '@site/src/components/EmailSignupForm/EmailSignupForm';
 
-This book is for anyone who is interested in computing and wants to learn more about the exciting, but sometimes daunting, world of _The Shell_. The shell is simple interface for working with computers and programs and learning some of its features can enormously increase your productivity as any computer user - whether a home user or hobbyist, programmer, data scientist, writer, administrator or other professional.
+Investing just a few hours your ability to use text based interfaces for your computer can have an enormous impact on your productivity. It can also make your work more fun, allowing you to maintain that creative 'flow' state that can make technology so exciting.
 
-For the newcomer, you'll learn what a shell is, how to use it on your system, and then how to become more effective everyday by integrating the shell into your work. For the experienced professional, there is a wealth of detailed tips and tricks in each chapter that go into advanced topics and techniques to make you even more of a power user.
-
-If you are new to shell, I recommend starting at the beginning with the [Getting Started](./01-transitioning-to-the-shell/01-getting-started/index.md) page, to set up your machine and work forwards from there.
+I've been lucky enough to spend many years working as a software engineer, but also with scientists, data engineers, site reliability engineers and technologists of all sorts. One thing that has stood out about great technologists has been their ability to make their tools work for them, stitching them together in creative ways that suits their style.
 
-If you are already comfortable with running a shell, know what `bash` is, and know how to run basic commands like `ls` and `cd`, are familiar with terms like _command_ and _parameter_ then you can skip through some of the earlier sections and pick up the chapters which sound most interesting to you. The goal of this book is to be a collection of small, contained tutorials on how to use the shell more effectively, you can go through it sequentially or just pick and choose the sections which seem the most interesting.
+This is not a book on shell scripting or Linux administration! Each chapter in this book can be read as a standalone set of techniques to help you be more efficient, understand your system in more depth, and craft your environment to suit your working style. This book does not advocate that totally change the way you work or drop your current tooling; it just brings together a set of skills that you can add to your toolkit and incorporate in your own way.
 
 If you find this book useful, please consider sponsoring me to support my open source work:
 
 <iframe src="https://github.com/sponsors/dwmkerr/button" title="Sponsor dwmkerr" height="35" width="116" style={{border: 0}}></iframe>
 
-If you would like to get email updates when new chapters are published, please do provide your email below. I won't be using it for anything beyond updates to the book.
+## Who Should Read This Book
 
-<EmailSignupForm />
+Developers and engineers should find almost every chapter of this book immediately applicable in day-to-day work. Whether you use Python, Golang, .NET, Java, whether you use an IDE or the terminal, these skills will help in day-to-day work.
+
+Site reliability engineers, system administrators and DevSecOps professionals will find these skills essential - if you regularly administer remote machines, connect to containers, manage clusters or cloud environments, you will find many techniques to help you with your work.
+
+Hobbyists, polymaths and explorers should also read on - as well as going into specific techniques, each chapter gives essential knowledge on how these computers, operating systems and networking works.
+
+## What's In This Book? 
+
+Each chapter of this book aims to work as a stand-alone description of a set of techniques that you should be able to apply immediately. I have focused on keeping the information to the essentials that allow you to use the skill, rather than create an exhaustive description of every possible feature. This should allow you to pick up the book and read a chapter over a coffee and try out the skills straight away.
+
+ - [_Part 1 - Transitioning to the Shell_](./01-transitioning-to-the-shell/index.md) is aimed at people who are new to the shell. You'll learn how to set up your environment, navigate your system, manage files, move between a desktop environment and the shell and how to get help. More advanced users may want to skip some of this content.
+ - [_Part 2 - Core Skills_](./02-core-skills/index.md) introduces the essential techniques that you should be able to apply immediately to improve your productivity. You'll learn how to use pipelines, rapidly move around the command-line and commands quickly, manage multiple tasks in parallel with jobs, the different types of commands that are available and how to search for files.
+ - [_Part 3 - Manipulating Text and Streams_](./03-manipulating-text/index.md) demonstrates many techniques to work with text -whether it's code, data or configuration. You'll learn how to use regular expressions, how to search through text, how to slice and dice text, how to manipulate code and data, and then how to apply these techniques to your shell commands themselves.
+ - [_Part 4 - Shell Scripting_](./04-shell-scripting/index.md) is a crash course in shell scripting. You'll learn how to write and run scripts, read and process input, perform logical operations, iterate over files and folders, build functions, handle errors and a set of re-usable patterns you can apply to your own scripts.
+ - [_Part 5 - Building Your Toolkit_](./05-building-your-toolkit/index.md) goes into the techniques you can use to create and customize your own environment. You'll learn how to configure the shell, customize your command prompt, manage your configuration files and share and manage your configuration with the Git version control system.
+ - [_Part 6 - Advanced Techniques_](./06-advanced-techniques/index.md) introduces even more powerful tools and techniques, showing the fundamentals of each skill and how you might incorporate it into your work. You'll learn how shell expansion works, which is key to understanding many of the nuances of complex commands, when you should move away from shell scripts and into a full-blown programming language, how to build programs that integrate well into other tools in the shell, how to connect to other machines with the secure shell, how to use the popular terminal editor Vim and how to use terminal multiplexers. 
+
+For the newcomer, you'll learn what a shell is, how to use it on your system, and then how to become more effective everyday by integrating the shell into your work. For the experienced professional, there is a wealth of detailed tips and tricks in each chapter that go into advanced topics and techniques to make you even more of a power user.
+
+## What You'll Need
+
+If you are using a computer, you have enough to get started! In [_Chapter 1 - Setting Up Your Shell Environment_](./01-transitioning-to-the-shell/01-getting-started/index.md) you'll learn how to setup your shell in Windows, Linux or MacOS. 
 
-This book is also open source! The code is on [github.com/dwmkerr/effective-shell](https://github.com/dwmkerr/effective-shell). Feel free to use the 'Comments' section at the bottom of each page to discuss the content, or even [open a pull request](https://github.com/dwmkerr/effective-shell/pulls) to propose changes.
+No Linux, shell or programming knowledge is required to use this book, all underlying concepts will be explained as we go along. Advanced users will be able to skip some of the explanations, but there is also enough depth in each chapter that users of all levels should be able to learn something new. 
 
-All of the content of this book is designed to be suitable to work with Microsoft Windows, Mac OS and Linux. So no matter what system you are running, you should be able to follow along. We will focus primarily on 'Linux Like' environments, which hopefully will give you the skills which you can apply most widely. For Windows, we'll look into how to tweak your system to be able to run all of the samples.
+## How To Read This Book
+
+Commands that you can type into your shell, such as `grep` are shown as `monospaced text`. Paths to file and folders, such as the _~/effective-shell_ folder are shown in _italics_.
+
+In larger code samples, the dollar sign is used to indicate where you would start typing - this is the command prompt. The text that you type is shown in `**bold**`:
+
+<pre>
+$ <strong>echo "my shell is $SHELL"</strong><br />
+my shell is /bin/bash<br />
+</pre>
+
+This book assumes that you are using a Bash-like shell, most of these shells should operate in a similar way. However, given the popularity of the Z shell (Zsh) are called out like so:
+
+:::info Z shell
+
+Z shell specifics are highlighted like this.
+
+:::
+
+## Email Updates
+
+If you would like to get email updates when new chapters are published, please do provide your email below. I won't be using it for anything beyond updates to the book.
+
+<EmailSignupForm />