There are no ads promoted in WhatsApp, so how does WhatsApp get money (money)? Explain with information explaining.

We will get the solution when we look at the matter a bit differently.
In fact, when we use WhatsApp or messenger, we think we're using a product. But the fact is that we ourselves are using the product and these companies use our information very dirtyly.
So we are using our personal information as much as we are free to use.
Think once that your child or younger brother may have done something bad and he is filing remorse for that work. After learning about such a situation, a militant group started campaigning with them saying that fight Jihad, washing all the sins and leaving you in Paradise.
This is an example to illustrate the terrible situation. But these advertising companies actually get into our personal words through their shrewd app and by selling the information to such brokers according to the information type.
We also feel free to keep reading all day, without personal interaction, personal interactions, and even pictures of personal moments can not be transferred through them.
As much as you are aware, the less used, and the more secure. Hope you understand now that WhatsApp and Facebook make billions of billions of dollars.