I'm very new to Ubuntu, programming, and general computer software lingo (as in today) and I am doing a project that requires I use programs that run best in Ubuntu. My main computer is Windows. Is there a way for me to efficiently toggle between operating systems without having to make one default? Specifically, I have an external hard drive. Is there a way to plug in the hard drive and boot the Linux OS from there, and store all the related program files on there instead of my main OS? Thanks!