These are a few of examples of web scraping for a blog post.
Most will require installing a package using the language's package manager. The
easy_install commands should be readily available for those on Mac or Linux machines. For Windows users, you may be better off searching for instructions online or finding a way to download and import the package manually.
If one of the packages fails to install, chances are you need root privileges. Try re-running the command prefixed with
sudo and enter your password at the prompt, e.g.
sudo gem install nokogiri.