Or IE7 circa 2006. IE7 separated its UI and browser content in different processes. IE8+ group several tabs into one process when passing a threshold. This is much better for battery life compare to Chrome process-per-tab.
In both IE 8-11 and Chrome 1+ there are several tabs per sub-process. Chrome comes even with its own "Taskmanager" where you can see which tab sits in which process and how many resources it takes. You can find the Taskmanager in the Chrome's "Tools" sub-menu.