[TYPO3] menu - how to count and display included subpages?

[rene]

Peter Klein wrote:
> Hi rene. If you change my example a bit it will work in TMENU too..
> 
> Change "lib.test" to "stdWrap.cObject" and place the entire COA object 
> inside the "NO" part of your TMENU.. And drop the "page.30 < lib.test"
> 

hello peter. thank you! it works great. is there any description why
using this "cObject"? i thougt any object like TEXT or HTML are content
objects but why i have to use it again?

sorry for the stupid questions but i don't want to use someones scripts
without understanding how and why it works.