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+# How to turn these files into a book
+
+In this repostitory, you will find the chapters written in 
+[Markdown](https://daringfireball.net/projects/markdown/). Markdown files are pretty readable, but
+you may well want to convert the source files into other formats. There is a Makefile that you
+can use you do thay, but you will need various other tools installed. This file explains which
+tools are required, what they are required for and how o get them.
+
+## Make
+
+[Make](https://en.wikipedia.org/wiki/Make_%28software%29) is the standard Unix tool for controlling
+how to build files from other files. If you're using a system based on Unix (that includes Linux,
+BSD and OSX) then you will almost certainly alread have Make installed. If you're using Windows,
+then I think that Microsoft have a similar tool called `nmake` which you can almost certainly
+download from one of their many web sites.
+
+## Pandoc
+
+The first file that we need to generate is the [EPUB](https://en.wikipedia.org/wiki/EPUB) version
+of the book. And for that we use a tool called [Pandoc](http://pandoc.org/). This almost certainly
+won't already be installed on your system.
+
+For Linux users, Pandoc will be available in your system's package repository. If you're using
+a RedHat/Fedora/Centos system you can install it with `sudo install pandoc`. For a Debian/Ubuntu
+system, the equivalent command is `sudo apt-get install pandoc`. If you're using any other kind of
+Linux then I'm sure you're clever enough to work out the equivalent command,
+
+For OSX and Windows users, there are installable packages of the latest version of Pandoc available
+from their [Github repository](https://github.com/jgm/pandoc/releases/latest). Simply download the
+correct file and double-click it.
+
+Once you have Make and Pandoc installed, you can build an EPUB of the book by opening a terminal,
+changing to the directory where you have checked out a copy of this repository and typing:
+
+    make epub
+
+Or, even, just:
+
+    make
+
+You will end up with a file called perlwebbook.epub which can be used in many ebook systems.
+
+## Kindlegen
+
+If you want to generate a copy of the book which you can read on an Amazon Kindle, then you
+need to go a step further an generate a [MOBI](https://en.wikipedia.org/wiki/Mobipocket) version
+of the file. We do this using a program called Kindlegen which Amazon makes available for many
+different platforms. You can download the program
+[from their web site](http://www.amazon.com/gp/feature.html?docId=1000765211).
+
+Once you have installed Kindlegen, you can generate your MOBI file by opening a terminal, changing
+to the directory where you have checked out a copy of this repository and typing:
+
+    make mobi
+
+**Note:** The MOBI is generated by converting the EPUB. So running `make mobi` will automatically
+run `make epub` first, which means that you will also need to install Pandoc as described above.
+
+## Calibre
+
+Sometimes you don't want a real ebook version of the book. Sometimes just a
+[PDF](https://en.wikipedia.org/wiki/Portable_Document_Format) is enough. So our Make system
+supports building a PDF too.
+
+Building a PDF uses another tool called [Calibre](http://calibre-ebook.com/) which you will need to
+install if you want to make a PDF.
+
+For Linux users, Calibre will be available in your system's package repository. If you're using
+a RedHat/Fedora/Centos system you can install it with `sudo install calibre`. For a Debian/Ubuntu
+system, the equivalent command is `sudo apt-get install calibre`. If you're using any other kind of
+Linux then I'm sure you're clever enough to work out the equivalent command,
+
+For OSX and Windows users, there are installable packages of the latest version of Calibre available
+from their [web site](http://calibre-ebook.com/download). Simply download the correct file and
+double-click it.
+
+Once you have Calibre installed, you can build a PDF of the book by opening a terminal, changing to
+the directory where you have checked out a copy of this repository and typing:
+
+    make pdf
+
+**Note:** The PDF is generated by converting the EPUB. So running `make mobi` will automatically
+run `make epub` first, which means that you will also need to install Pandoc as described above.
+
+## Conversion Process
+
+This section summarises the software needed to convert the input files into various output files.
+
+* This repository contains the book's sources in Markdown format.
+* An EPUB is created from the Markdown using Pandoc
+* A MOBI is created from the EPUB using Kindlegen
+* A PDF is created from the EPUB using Calibre