Chrome is a major player in the browser market today with 53 percent share on desktops (source: Statcounter, April '15). It's an excellent browser on the whole but it can consume cast amounts of memory - particularly for those of us that have multiple tabs open simultaneously.
Through a rather intuitive interface, users can opt to auto-suspend tabs after a configurable period of time or set them to suspended manually. Tabs can also be whitelisted to avoid automatic suspension. Those suspended tabs, however, are retained after closing and reopening the browser, preventing many tabs from all reloading after a restart.
There are other Chrome extensions which provide related functionality, including Tab Hibernation, OneTab, Tabs Outliner, and TooManyTabs.