I'm not an expert user on ubuntu.
I installed rvm to instal ruby and ruby on rails on a machine (virtual machine, in the cloud, ubuntu 10.04).
So after instalaltion, I rvm command was not recognized and I read in stack overflow, the I should check the 'Run command as logn shell' option in gnome-terminal, so I did.
After that none of the /usr/bin commands are being recognized anymore.
Command 'apt-get' is available in '/usr/bin/apt-get' The command could not be located because '/usr/bin' is not included in the PATH environment variable. apt-get: command not found