Answers for "check all ruby versions"

how to check ruby version

// Command line:
$ ruby -v

// Within irb type "RUBY_VERSION"
# => "2.4.1"

// If using RVM:
$ rvm current
# => ruby-2.4.1

manage ruby versions

$ rbenv versions
  1.8.7-p352
  1.9.2-p290
* 1.9.3-p327 (set by /Users/sam/.rbenv/version)
  jruby-1.7.1
  rbx-1.2.4
  ree-1.8.7-2011.03