Who can see my pictures on Facebook

Depends how the settings you have selected for your profile.
Read more here: http://www.facebook.com/help/privacy
And
http://techland.time.com/2013/04/04/facebook-privacy-settings-guide/

Many people, including my son and myself are not on Facebook any longer because prospective employers can 'demand' to see an applicant's history on Facebook. So everything that is there has to be squeaky clean.