Merge pull request #526 from jviereck/docs

Add some more docs to the Readme.md

README.md

@@ -27,6 +27,32 @@ For an online demo, visit:
 This demo provides an interactive interface for displaying and browsing PDFs
 using the pdf.js API.
 
+**Getting the code**
+
+To get a local copy of the current code, clone it using git:
+
+```bash
+    git clone git://github.com/andreasgal/pdf.js.git pdfjs
+    cd pdfjs
+```
+
+Next, you need to start a local web server as some browsers don't allow opening
+PDF files for a file:// url:
+
+```bash
+  make server
+```
+
+If everything worked out, you can now serve 
+
+  http://localhost:8888/web/viewer.html
+
+You can also view all the test pdf files on the right side serving
+
+  http://localhost:8888/test/pdfs/?frame
+
+
+
 **Hello world**
 
 For a "hello world" example, take a look at:
@@ -38,6 +64,20 @@ in a custom project.
 
 
 
+## Contributing
+
+pdf.js is a community-driver project, so contributors are always welcome. 
+Simply fork our repo and contribute away. A great place to start is our
+open issues. For better consistency and long-term stability, please do look around the 
+code and try to follow our conventions.
+
+If you __don't want to hack__ on the project or have short spare times, you still
+can help! Just open PDFs in the 
+[online demo](http://andreasgal.github.com/pdf.js/web/viewer.html) and report 
+any breakage in rendering.
+
+
+
 ## Running the Tests
 
 pdf.js comes with browser-level regression tests that allow one to probe 
@@ -64,16 +104,6 @@ images. The test type `load` simply tests whether the file loads without
 raising any errors.
 
 
-## Contributing
-
-pdf.js is a community-driver project, so contributors are always welcome. 
-Simply fork our repo and contribute away. A great place to start is our
-open issues. 
-
-For better consistency and long-term stability, please do look around the 
-code and try to follow our conventions.
-
-
 ## Additional resources
 
 Our demo site is here:
@@ -97,8 +127,28 @@ Join our mailing list:
 Subscribe either using lists.mozilla.org or Google Groups: 
   
   https://lists.mozilla.org/listinfo/dev-pdf-js
+
   https://groups.google.com/group/mozilla.dev.pdf-js/topics
 
 Talk to us on IRC:
 
   #pdfjs on irc.mozilla.org
+  
+## Additional resources to understand the structure of PDF
+
+A really basic overview of PDF is described here:
+
+  http://partners.adobe.com/public/developer/en/livecycle/lc_pdf_overview_format.pdf
+
+A more detailed file example:
+
+  http://gnupdf.org/Introduction_to_PDF
+  
+The PDF specification itself is an ISO and not free available. However, there is
+a "PDF Reference" from Adobe:
+
+  http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/devnet/pdf/pdfs/pdf_reference_1-7.pdf
+
+Recommanded chapters to read: "2. Overview", "3.4 File Structure", 
+"4.1 Graphics Objects" that lists the PDF commands.
+