irb not found when installing Ruby 1.9.3

I installed RVM onto my Ubuntu 11.10 VirtualBox VM and proceeded to use it to install Ruby 1.9.3. This was in order to follow Learn Ruby The Hard Way but the problem was when trying to follow the tutorial where it told me to type in either ruby -v or irb. Both returned “Command not recognised”. Turns out you have to tell RVM which version of Ruby to use by default. You do this by typing the following into a bash shell:

rvm --default use 1.9.3

Jason Edwards