Do all Nokia phones use Symbian as their OS?

Do all Nokia smartphones use Symbian (OS) as their operating system?

Also, if Nokia phones have Symbian as their OS, what do Samsung phones have as theirs?

Thanks to anyone who might share info about this.

no some nokia phones use symbian as their os but some run on java plateform...
For ex. N70,5800xm r symbian fones but 6300,x2 are java one's...
And about samsung...
Samsung's past fones use java but after sometime they started using android as their os...and now samsung has its own os i.e. Bada which is used in some samsung fones....
Hope u r satisfied....
And as per the latest news nokia is gonna collaborate with windows n after some time u r going to see nokia phones with windows os....