about O-1 visa

What is the difference between O-1 and H1b visa?
The O-1 visa will last how long?
How many times can O-1 visa be renewed?
How easy switch O-1 to other visa types?
Any further information?
Thanks in advance.

所有跟帖： 

• 回複：about O-1 visa -whynotgreentea- ♀ (187 bytes) () 04/03/2008 postreply 09:15:27

• Thank you very much! -handfree- ♂ (0 bytes) () 04/03/2008 postreply 09:39:27