Suspend-to-RAM (STR) occurs when a system enters a low-power state. Information on system configuration, open applications, and active files is stored in main memory (RAM ), while most of the system's other components are turned off. A system in STR can use as little as 5 watts of power, with most of it going to main memory for data maintenance.
If left in STR, a system may be programmed to waken, so it can perform tasks at any given time. If the power is interrupted, then the system will undergo a normal reboot, restoring full power to the machine and loosing any information not saved to the hard disk.