Hibernate, Standby, Suspend and Sleep

Hibernate, Standby, Suspend and Sleep in Xubuntu

'Hibernate' is frequently disabled in Linux because some BIOSes / kernel combinations cannot handle it. It is the mode whereby everything in RAM is stored on disc, then the PC powers off. On powering up, the contents of RAM are recovered from the disc and everything carries on as it was before. Powering off and on each may take a couple of minutes.

'Suspend' is where most components are powered down, such as the disc drive and the screen, and so remaining power or battery charge is used to retain the contents of RAM. If the power goes off or the battery runs out, you lose what you were doing.

$> pm-is-supported 
pm-is-supported [--suspend | --hibernate | --suspend-hybrid ]

$>

pm-suspend-hybrid does both.

Link: http://www.cyberciti.biz/faq/linux-command-to-suspend-hibernate-laptop-netbook-pc/