What are the standards for creating banners in Photoshop?Thanks.
None that I know of. Do you have a more specific question? What are you trying to do?
The only standards I can think of with regards to banner ads are the IAB standards that set sizes commonly used, and a descriptive term for the format. They also make recommendations on frame rates and other technical parameters that primarily relate to flash adverts rather than anything photoshop would output.
The "standards" are commonly known to be as long as a piece of string.
There are some pre-installed banners, but without knowing more I don't know if we're talking web banners or print banners. There's a slight difference in dimensions there...