What is RVM and why should you use it? RVM is a Ruby interpreter, version management tool. In short, it enables you to switch between different versions and releases of Ruby (for instance, version 1.8.6, 1.8.7, jruby 1.9.2, ruby enterprise edition) on the...

If you want to get version information about a gem the easiest way to do it is with this command gem list For example gem list activemerchant will output the activemerchant versions I have installed. You can pass only part of the name like gem list ...