require 'mime/types'

   plaintext = MIME::Types['text/plain'] # => [ text/plain ]
   text = plaintext.first
   puts text.media_type            # => 'text'
   puts text.sub_type              # => 'plain'

   puts text.extensions.join(' ')  # => 'txt asc c cc h hh cpp hpp dat hlp'
   puts text.preferred_extension   # => 'txt'
   puts text.friendly              # => 'Text Document'
   puts text.i18n_key              # => 'text.plain'

   puts text.encoding              # => quoted-printable
   puts text.default_encoding      # => quoted-printable
   puts text.binary?               # => false
   puts text.ascii?                # => true
   puts text.obsolete?             # => false
   puts text.registered?           # => true
   puts text.complete?             # => true

   puts text                       # => 'text/plain'

   puts text == 'text/plain'       # => true
   puts 'text/plain' == text       # => true
   puts text == 'text/x-plain'     # => false
   puts 'text/x-plain' == text     # => false

   puts MIME::Type.simplified('x-appl/x-zip') # => 'x-appl/x-zip'
   puts MIME::Type.i18n_key('x-appl/x-zip') # => 'x-appl.x-zip'

   puts text.like?('text/x-plain') # => true
   puts text.like?(MIME::Type.new('x-text/x-plain')) # => true

   puts text.xrefs.inspect # => { "rfc" => [ "rfc2046", "rfc3676", "rfc5147" ] }
   puts text.xref_urls # => [ "http://www.iana.org/go/rfc2046",
                       #      "http://www.iana.org/go/rfc3676",
                       #      "http://www.iana.org/go/rfc5147" ]

   xtext = MIME::Type.new('x-text/x-plain')
   puts xtext.media_type # => 'text'
   puts xtext.raw_media_type # => 'x-text'
   puts xtext.sub_type # => 'plain'
   puts xtext.raw_sub_type # => 'x-plain'
   puts xtext.complete? # => false

   puts MIME::Types.any? { |type| type.content_type == 'text/plain' } # => true
   puts MIME::Types.all?(&:registered?) # => false

   # Various string representations of MIME types
   qcelp = MIME::Types['audio/QCELP'].first # => audio/QCELP
   puts qcelp.content_type         # => 'audio/QCELP'
   puts qcelp.simplified           # => 'audio/qcelp'

   xwingz = MIME::Types['application/x-Wingz'].first # => application/x-Wingz
   puts xwingz.content_type        # => 'application/x-Wingz'
   puts xwingz.simplified          # => 'application/x-wingz'