The Ruby Programming Language

Try Ruby

We hope our tour of Ruby’s key features has piqued your interest and you are eager to try Ruby out. To do that, you’ll need a Ruby interpreter, and you’ll also want to know how to use three tools—irb, ri, and gem—that are bundled with the interpreter. This section explains how to get and use them.

The Ruby Interpreter

The official web site for Ruby is http://www.ruby-lang.org. If Ruby is not already installed on your computer, you can follow the download link on the ruby-lang.org home page for instructions on downloading and installing the standard C-based reference implementation of Ruby.

Once you have Ruby installed, you can invoke the Ruby interpreter with the ruby command:

% ruby -e 'puts "hello world!"'
hello world!

The -e command-line option causes the interpreter to execute a single specified line of Ruby code. More commonly, you’d place your Ruby program in a file and tell the interpreter to invoke it:

% ruby hello.rb
hello world!

Other Ruby Implementations

In the absence of a formal specification for the Ruby language, the Ruby interpreter from ruby-lang.org is the reference implementation that defines the language. It is sometimes known as MRI, or “Matz’s Ruby Implementation.” For Ruby 1.9, the original MRI interpreter was merged with YARV (“Yet Another Ruby Virtual machine”) to produce a new reference implementation that performs internal compilation to bytecode and then executes that bytecode on a virtual machine.

The reference implementation is not the only one available, ...