subcategory
when devideing things in categories, we have some subcategories as well. What do we call those subcategories which are more important or less important than other subcategories.Do we say main subcategories? what do we say for less important subcategories?
DO we have have soth like A-level subcategories or B-Level subcategories?

Question

subcategory 
when devideing things in categories, we have some subcategories as well. What do we call those subcategories which are more important or less important than other subcategories.Do we say main subcategories? what do we say for less important subcategories?
DO we have have soth like A-level subcategories or B-Level subcategories?

Answer

You could use primary, secondary, tertiary, etc. sub-category if you wished but mudy shaw is right.  There really is nothing specific in English to distinguish these from each other.  You normally deal with this typographically - in the table of contents or similiar, etc.

Answer

Well there aren't any special names for those subcategories as far as I know. It's up to u to name those subcategories as u like.

It sounds like a good idea if u want to adopt names like "A-Level or B-Level". It will make ur job easier.

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