diff --git a/default_conf.py b/default_conf.py
index e1b94b7..3c42a1e 100644
--- a/default_conf.py
+++ b/default_conf.py
@@ -17,7 +17,7 @@ META_PATH = os.path.join(DB_ROOT, 'meta.db')
 # Database filename per month
 DB_FILENAME = 'iwla.db'
 
-# Web server log format (nginx style). Default is what apache log
+# Web server log format (nginx style). Default is apache log format
 log_format = '$server_name:$server_port $remote_addr - $remote_user [$time_local] ' +\
     '"$request" $status $body_bytes_sent ' +\
     '"$http_referer" "$http_user_agent"'
@@ -30,7 +30,7 @@ pre_analysis_hooks = []
 post_analysis_hooks = []
 display_hooks = []
 
-# Extensions that are considered as a HTML page (or result)
+# Extensions that are considered as a HTML page (or result) in opposite to hits
 pages_extensions = ['/', 'htm', 'html', 'xhtml', 'py', 'pl', 'rb', 'php']
 # HTTP codes that are cosidered OK
 viewed_http_codes = [200, 304]
@@ -49,7 +49,7 @@ icon_path = '%s/%s' % (os.path.basename(resources_path[0]), 'icon')
 # CSS path (you can add yours)
 css_path = ['%s/%s/%s' % (os.path.basename(resources_path[0]), 'css', 'iwla.css')]
 
-# Extensions to compress in gzip during display build
+# Files extensions to compress in gzip during display build
 compress_output_files = []
 
 # Path to locales files
diff --git a/docs/main.md b/docs/main.md
index 389e653..8fe2240 100644
--- a/docs/main.md
+++ b/docs/main.md
@@ -4,14 +4,14 @@ iwla
 Introduction
 ------------
 
-iwla (Intelligent Web Log Analyzer) is basically a clone of [awstats](http://www.awstats.org). The main problem with awstats is that it's a very monolothic project with everything in one big PERL file. In opposite, iwla has be though to be very modulor : a small core analysis and a lot of filters. It can be viewed as UNIX pipes. Philosophy of iwla is : add, update, delete ! That's the job of each filters : modify statistics until final result.
+iwla (Intelligent Web Log Analyzer) is basically a clone of [awstats](http://www.awstats.org). The main problem with awstats is that it's a very monolothic project with everything in one big PERL file. In opposite, iwla has be though to be very modular : a small core analysis and a lot of filters. It can be viewed as UNIX pipes. Philosophy of iwla is : add, update, delete ! That's the job of each filters : modify statistics until final result.
 
 Nevertheless, iwla is only focused on HTTP logs. It uses data (robots definitions, search engines definitions) and design from awstats. Moreover, it's not dynamic, but only generates static HTML page (with gzip compression option).
 
 Usage
 -----
 
-./iwla [-c|--clean-output] [-i|--stdin] [-f FILE|--file FILE] [-d LOGLEVEL|--log-level LOGLEVEL]
+    ./iwla [-c|--clean-output] [-i|--stdin] [-f FILE|--file FILE] [-d LOGLEVEL|--log-level LOGLEVEL]
 
     -c : Clean output (database and HTML) before starting
     -i : Read data from stdin instead of conf.analyzed_filename
@@ -21,54 +21,72 @@ Usage
 Basic usage
 -----------
 
-In addition to command line, iwla read parameters in _ default_conf.py _. User can override default values using _conf.py_ file. Each module requires its own parameters.
-Main valued to edit are :
-    analyzed_filename : web server log
-    domaine_name : domain name to filter
-    pre_analysis_hooks
-    post_analysis_hooks
-    display_hooks
-    locale
+In addition to command line, iwla read parameters in default_conf.py. User can override default values using _conf.py_ file. Each module requires its own parameters.
+
+Main values to edit are :
+
+  * **analyzed_filename** : web server log
+  * **domaine_name** : domain name to filter
+  * **pre_analysis_hooks** : List of pre analysis hooks
+  * **post_analysis_hooks** : List of post analysis hooks
+  * **display_hooks** : List of display hooks
+  * **locale** : Displayed locale (_en_ or _fr_)
+
+Then, you can then iwla. Output HTML files are created in _output_ directory by default. To quickly see it go in output and type
 
-You can then launch iwla. Output HTML files are created in _output_ directory by default. To quickly see it go in output and type
     python -m SimpleHTTPServer 8000
+
 Open your favorite web browser at _http://localhost:8000_. Enjoy !
 
+**Warning** : The order is hooks list is important : Some plugins may requires others plugins, and the order of display_hooks is the order of displayed blocks in final result.
+
+
 Interesting default configuration values
 ----------------------------------------
 
-    DB_ROOT : Default database directory
-    DISPLAY_ROOT : Default HTML output directory
-    log_format : Web server log format (nginx style). Default is what apache log
-    time_format : Time format used in log format
-    pages_extensions : Extensions that are considered as a HTML page (or result)
-    viewed_http_codes : HTTP codes that are cosidered OK
-    count_hit_only_visitors : If False, doesn't cout visitors that doesn't GET a page but resources only (images, rss...)
-    multimedia_files : Multimedia extensions (not accounted as downloaded files)
-    css_path : CSS path (you can add yours)
-    compress_output_files : Extensions to compress in gzip during display build
+  * **DB_ROOT** : Default database directory (default ./output_db)
+  * **DISPLAY_ROOT** : Default HTML output directory (default ./output)
+  * **log_format** : Web server log format (nginx style). Default is apache log format
+  * **time_format** : Time format used in log format
+  * **pages_extensions** : Extensions that are considered as a HTML page (or result) in opposit to hits
+  * **viewed_http_codes** : HTTP codes that are cosidered OK (200, 304)
+  * **count_hit_only_visitors** : If False, doesn't cout visitors that doesn't GET a page but resources only (images, rss...)
+  * **multimedia_files** : Multimedia extensions (not accounted as downloaded files)
+  * **css_path** : CSS path (you can add yours)
+  * **compress_output_files** : Files extensions to compress in gzip during display build
 
 Plugins
 -------
 
-As previously described, plugins acts like UNIX pipes : final statistics are constantly updated by each plugin to produce final result. We have three type of plugins :
-    Pre analysis plugins : Called before generating days statistics. They are in charge to filter robots, crawlers, bad pages...
-    Post analysis plugins : Called after basic statistics computation. They are in charge to enlight them with each own algorithms
-    Display plugins : They are in charge to produce HTML files from statistics.
+As previously described, plugins acts like UNIX pipes : statistics are constantly updated by each plugin to produce final result. We have three type of plugins :
 
-To use plugins, just insert their name in pre_analysis_hooks, post_analysis_hooks and display_hooks list.
+  * **Pre analysis plugins** : Called before generating days statistics. They are in charge to filter robots, crawlers, bad pages...
+  * **Post analysis plugins** : Called after basic statistics computation. They are in charge to enlight them with their own algorithms
+  * **Display plugins** : They are in charge to produce HTML files from statistics.
+
+To use plugins, just insert their name in _pre_analysis_hooks_, _post_analysis_hooks_ and _display_hooks_ lists in conf.py.
+
+Statistics are stored in dictionaries :
+
+  * **month_stats** : Statistics of current analysed month
+  * **valid_visitor** : A subset of month_stats without robots
+  * **days_stats** : Statistics of current analysed day
+  * **visits** : All visitors with all of its requests
+  * **meta** : Final result of month statistics (by year)
 
 Create a Plugins
 ----------------
 
-To create a new plugin, it's necessary to create a derived class of IPlugin (_iplugin.py) in the right directory (_plugins/xxx/your_plugin.py_).
+To create a new plugin, it's necessary to create a derived class of IPlugin (_iplugin.py) in the right directory (_plugins/xxx/yourPlugin.py_).
 
 Plugins can defines required configuration values (self.conf_requires) that must be set in conf.py (or can be optional). They can also defines required plugins (self.requires).
 
-For display plugins, a lot of code has been wrote in _display.py_ that simplify the creation on HTML blocks, tables and graphs.
+The two functions to overload are _load(self)_ that must returns True or False if all is good (or not). It's called after _init_. The second is _hook(self)_ that is the body of plugins.
 
-Modules
--------
+For display plugins, a lot of code has been wrote in _display.py_ that simplify the creation on HTML blocks, tables and bar graphs.
+
+Plugins
+=======
 
 Optional configuration values ends with *.
 
diff --git a/tools/extract_doc.py b/tools/extract_doc.py
index 0f5fbc3..eee534b 100755
--- a/tools/extract_doc.py
+++ b/tools/extract_doc.py
@@ -8,10 +8,11 @@ if filename.endswith('__init__.py'):
     sys.exit(0)
 
 package_name = filename.replace('/', '.').replace('.py', '')
-sys.stdout.write('**%s**' % (package_name))
-sys.stdout.write('\n\n')
-# sys.stdout.write('-' * len(package_name))
+sys.stdout.write('%s' % (package_name))
+sys.stdout.write('\n')
 # sys.stdout.write('\n\n')
+sys.stdout.write('-' * len(package_name))
+sys.stdout.write('\n\n')
 
 sys.stderr.write('\tExtract doc from %s\n' % (filename))
 
@@ -24,6 +25,6 @@ with open(filename) as infile:
             else:
                 break
         elif copy:
-            sys.stdout.write(line)
+            sys.stdout.write('    %s' % (line))
 
 sys.stdout.write('\n\n')