Can you provide examples of parsing HTML?

Question

How do you parse HTML with a variety of languages and parsing libraries?

---

When answering:

Individual comments will be linked to in answers to questions

Answer 1

Language: Ruby
Library: Nokogiri

#!/usr/bin/env ruby
require 'nokogiri'
require 'open-uri'

document = Nokogiri::HTML(open("http://google.com"))
document.css("html head title").first.content
=> "Google"
document.xpath("//title").first.content
=> "Google"