RVM is an environment manager for Ruby. With RVM you can handle different versions of Ruby and different gemsets on the same machine.

With this command you can install the tool on your machine.

bash -s stable < <(curl -s https://raw.github.com/wayneeseguin/rvm/master/binscripts/rvm-installer)
source ~/.bash_profile

If you want to install a special ruby version on your machine, just try this:

rvm install 1.9.2

And RVM will install Ruby version 1.9.2 on you machine. Everything what RVM is downloading and installing is stored in your home directory under “~/.rvm”. You can now also install version 1.8.7.

rvm install 1.8.7

With this command you can see all your versions.

rvm list

That will list all installed ruby versions. If you want to use version 1.9.2, just type in:

rvm use 1.9.2

That’s it 🙂

You can also create different gemsets.

rvm gemset create rails2

That will create a sperate gemset. Yo can use in every project a different ruby version and a different gemset. To choose a special gemset just type:

rvm gemset use rails2

You can list all your gemsets with this command:

rvm gemset list

That is pretty useful!