running other older versions of python

[Skaperen]

i know what a virtual machine is. i've worked with them since 1976.

in Unix/Linux another kind of environment i have used for a couple decades is chroot (the BSD community calls it a "jail").

i already understand the details of these environments. i need to understand the details of an environment created by virtualenv. telling me that it is safe does not fulfill my need to know. i need to know all the details.