_config.yml

def some_function():
    interesting = False
    print 'This line is highlighted.'
    print 'This one is not...'
    print '...but this one is.'

default _config.yml setting

safe: true
lsi: false
pygments: true
simple_search: http://google.com/search
markdown: kramdown
paginate: 10
kramdown:
  extensions:
    - autolink
    - footnotes
    - smart
permalink: /:year/:month/:title.html
relative_permalinks: false
url: http://tigefa4u.github.io
#url: http://localhost:2106
#port: 2106
#baseurl: /project-name
name: tigefa4u.Github
timezone:    Aisa/Jakarta
# Themes are encouraged to use these universal variables 
# so be sure to set them if your theme uses them.
title : tigefa4u.Github
tagline: love Github repositories
author :
  name : sugeng tigefa
  email : tigefa@gmail.com
  tumblr: tigefa
  flickr: tigefa
  github : tigefa4u
  repository: tigefa4u.github.io
  gittip: tigefa
  twitter : tigefa_team
  facebook: tigefa.team
  feedburner : tigefa4ugithub
  linkedin: tigefadotinfo
  googleplus: tigefa
  pinterest: tigefa
  bitbucket: tigefa4u
  stackoverflow: tigefa

# The production_url is only used when full-domain names are needed
# such as sitemap.txt 
# Most places will/should use BASE_PATH to make the urls
#
# If you have set a CNAME (pages.github.com) set your custom domain here.
# Else if you are pushing to username.github.io, replace with your username.
# Finally if you are pushing to a GitHub project page, include the project name at the end.
#
production_url : http://tigefa4u.github.io

# All Jekyll-Bootstrap specific configurations are namespaced into this hash
#
JB :
  version : 0.3.0

  # All links will be namespaced by BASE_PATH if defined.
  # Links in your website should always be prefixed with {{BASE_PATH}}
  # however this value will be dynamically changed depending on your deployment situation.
  #
  # CNAME (http://yourcustomdomain.com)
  #   DO NOT SET BASE_PATH 
  #   (urls will be prefixed with "/" and work relatively)
  #
  # GitHub Pages (http://username.github.io)
  #   DO NOT SET BASE_PATH 
  #   (urls will be prefixed with "/" and work relatively)
  #
  # GitHub Project Pages (http://username.github.io/project-name)
  #
  #   A GitHub Project site exists in the `gh-pages` branch of one of your repositories.
  #  REQUIRED! Set BASE_PATH to: http://username.github.io/project-name
  #
  # CAUTION:
  #   - When in Localhost, your site will run from root "/" regardless of BASE_PATH
  #   - Only the following values are falsy: ["", null, false]
  #   - When setting BASE_PATH it must be a valid url.
  #     This means always setting the protocol (http|https) or prefixing with "/"
  BASE_PATH : http://tigefa4u.github.io

  # By default, the asset_path is automatically defined relative to BASE_PATH plus the enabled theme.
  # ex: [BASE_PATH]/assets/themes/[THEME-NAME]
  #
  # Override this by defining an absolute path to assets here.
  # ex: 
  #   http://s3.amazonaws.com/yoursite/themes/watermelon
  #   /assets
  #
  ASSET_PATH : false

  # These paths are to the main pages Jekyll-Bootstrap ships with.
  # Some JB helpers refer to these paths; change them here if needed.
  #
  archive_path: /archive.html
  categories_path : /categories.html
  tags_path : /tags.html
  atom_path : /atom.xml
  rss_path : /rss.xml

  # Settings for comments helper
  # Set 'provider' to the comment provider you want to use.
  # Set 'provider' to false to turn commenting off globally.
  #
  comments :
    provider : disqus
    disqus :
      short_name : tigefa
#    livefyre :
#      site_id : 123
#    intensedebate :
#      account : 123abc
#    facebook :
#      appid : 123
#      num_posts: 5
#      width: 590
#      colorscheme: light
   
  # Settings for analytics helper
  # Set 'provider' to the analytics provider you want to use.
  # Set 'provider' to false to turn analytics off globally.
  #        
  analytics :
    provider : google 
    google : 
        tracking_id : 'UA-29791208-6'
#    getclicky :
#      site_id : 
#    mixpanel :
#        token : '_MIXPANEL_TOKEN_'
#    piwik :
#        baseURL : 'localhost/piwik' # Piwik installation address (without protocol)
#        idsite : '1'                   # the id of the site on Piwik

  # Settings for sharing helper. 
  # Sharing is for things like tweet, plusone, like, reddit buttons etc.
  # Set 'provider' to the sharing provider you want to use.
  # Set 'provider' to false to turn sharing off globally.
  # options ipost sharethis shareholic addthis
  sharing :
    provider : shareholic

# Settings for themes with bootswatch.com
# Set 'provider' to the themes provider you want to use.
# Set 'provider' to false to turn sharing off globally.
# Aviable themes slate cyborg flatly local cerulean simplex readable cosmo journal spacelab united
# view all demo themes http://bootswatch.com
# For local browsing without internet please set 'provider' local
  themes:
    provider: slate
    
  # Settings for all other include helpers can be defined by creating 
  # a hash with key named for the given helper. ex:
  #
  #   pages_list :
  #     provider : "custom"   
  #
  # Setting any helper's provider to 'custom' will bypass the helper code
  # and include your custom code. Your custom file must be defined at:
  #   ./_includes/custom/[HELPER]
  # where [HELPER] is the name of the helper you are overriding.
exclude: ["node_modules", "tigefa.jquery.json", "deploy.cmd", "composer.json", "circle.yml", "README", "iron.json", "bower.json", "params.json", ".coveralls.yml", ".travis.yml", ".gitignore", ".gitattributes", ".gitmodules", "README.md", "LICENSE", "Rakefile", "CHANGELOG.md", "Gemfile", "Gemfile.lock"]

jekyll config

more info about _config.yml

http://jekyllrb.com/docs/configuration/