Push switch across and it goes to sleep, push across and hold and it asks if you want to shutdown and does so with confirmation. Sleep = fast start and shutdown = all power off and longer start.
My 505 has never been turned off in three plus years apart from when installing firmware updates or PRS+ and I charge (separate PSU not computer) every week to ten days (overnight) with around 2+ hours reading per day (and I'm a fast reader so several hundred page turns).
