The capacity of fast SSD disks is usually limited (for technology- and price reasons) and so an additional 4 GB or 8 GB disk space can be quite useful. In most cases you can save several gigabytes of a precious disk space by deleting the system hibernation file.
Windows 7 create a hidden file hiberfil.sys in the root folder of disk C: - and the contents of RAM is stored into this file when your system gets hibernated. The hibernation makes your system start faster as the applications are not launched individually, but the system status is restored from the hibernation file image.
If you do not use hibernation to shutdown your system, or if the speed of the standard system start from a fast SSD disk is enough for you, you can delete (remove) the hibernation file. Depending on the size of RAM in your computer you can save several GB of free space on your SSD disk.
To disable hibernation and automatically delete the hiberfil.sys file, run the Windows command line (cmd.exe) as Administrator and enter the command:
powercfg.exe -h off
(to restore this function use the "on" option)