Chapter 5: Ruby In This Chapter Understanding the structure of a Ruby program Creating comments and declaring variables Using operators and data structures Branching and looping statements Creating functions and objects The Ruby programming language was created by Yukihiro “Matz” Matsumoto, a Japanese programmer who named the language after a gemstone in reference to the Perl (pearl) programming language. Although most languages focus on wringing out extra performance from computer hardware, Ruby focuses on a clean language syntax that’s easy for programmers to understand and use. Instead of trying to increase machine efficiency, Ruby tries to increase programmer efficiency. The overriding principle of Ruby is to create a language of least surprise, meaning that after you’re familiar with Ruby, you aren’t suddenly surprised that its features can be used in an entirely different way, which often occurs with languages such as C++. Ruby is an interpreted, object-oriented language for creating interactive Web pages. Although Ruby is similar to Perl and Python, Ruby abandons the C- syntax of Perl and more closely resembles the syntax of programming languages like Smalltalk or Ada. Instead of enclosing blocks of commands in curly brackets like C or Perl, Ruby encloses blocks of commands with keywords like Ada or more modern versions of BASIC. A programming framework, dubbed Ruby on Rails, makes it easy to manipulate databases through Web pages and has attracted the attention of many former Java programmers. Like Ruby itself, Ruby on Rails is free, which has further fueled its growth. Although still a relatively young language (created in 1995), Ruby has attracted a worldwide following and will likely play a major role in future applications developed for the Web. Mac OS X and many Linux distributions include an interpreter for the Ruby language. To get a copy of the free Ruby interpreter for other operating systems, visit the official Ruby Web site (www.ruby-lang.org).