$ sudo apt-get remove libssm0 

Uninstall libssm0 including dependent package

If you would like to remove libssm0 and it's dependent packages which are no longer needed from Ubuntu,

$ sudo apt-get remove --auto-remove libssm0 

Use Purging libssm0

If you use with purge options to libssm0 package all the configuration and dependent packages will be removed.

$ sudo apt-get purge libssm0 

If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.

$ sudo apt-get purge --auto-remove libssm0 

See Also,