Difference between "class" and "table"

There is no difference between class and table. Usually, "class" is used instead of "table" when talking about  the CUBRID Object Oriented model.

If you are reffering also to SQL grammar, I would add that while for the great majority of SQLs, "TABLE" and "CLASS" work absolutely the same, there are still some exceptions.

For example, the following statement does not work if you substitute "TABLES" with "CLASSES":

SHOW TABLES event;