Can I do permalinks without modifying the “.htaccess” file

Greetings,

I’ve just installed wordpress to the root directory two days ago. I am on yahoo webhosting and they don’t seem to want me messing with the “.htaccess” file for some reason. Am I able to get permalinks to work without adding anything to the “.htaccess” file? Also, is there other problems I will encounter with word press that I need to know about if I cannot get a writeable .htaccess file?

Thanks in advance.