Hi @mymy 

This is a great idea that Lucid could use to make improvements for all shapes in the future

Adding short, helpful hints that pop up when you hover over each element would make the user experience much better - especially for those who aren't familiar with the symbols used in business process mapping.

Would you prefer adding your idea in the below navigation to get this registered in your name.

Product feedback | Community (lucid.co)

Hope this helps - Happy to help further!!
Thank you very much and have a great one!
Warm regards

sorry I don’t have time, I just need that shape explanation, can you share with me?

@mymy You might find the following explanation helpful:

A Pool has two basic representations – “white-box” and “black-box”. White-box representation shows the internal details of the Pool, whereas a black-box representation hides any processes.

Black-box representation is best used when the Pool doesn’t reference a process but only an external process participant. Therefore, black-box pools are commonly named according to the process participant they represent, whereas white-box pools are commonly named according to the contained process.

Source

as a non english speaker that flies above my head. Do they mean black pool are for external participants to a company like suppliers?

Hi @mymy, that’s correct - black pools are to represent external participants whose processes you don’t need to display or know in detail. A supplier could be a good example of this. However, an external participant doesn’t have to have a black pool. Displaying process details within a pool might still be useful for an external participant if you want or need to have insight into them or they’re relevant to the other internal processes in your diagram. 

To summarize, a black pool is a pool where the contents is either unknown to you or out of your control, or irrelevant. Use it in a diagram when you want to refer to an external participant whose processes are out of your control or irrelevant to the diagram you are making.