Physical database storage for symbol type

For SQL Server 2005/2008, after some self-study, I am not sure if I know correctly how physically stored the character data type is. Please help view and comment. Here is my understanding, please review and feel free to correct me.

• when using a unicode character type (such as nvarchar), the base character is stored in UCS-2 encoding (that is, the character is physically stored as the corresponding UCS-2 bit-bits for the character). Collation defines collation and collation, no code page in this situation;

• when using a non-character character type (such as varchar), the base character is stored physically as bits defined in the corresponding code page specified by collation. So in this case the collation determines not only the comparison / collation, but also which code page (character, bit value represents a character and uses the same bit value to store the character in the physical memory of the database).

thanks in advance george