Where can I find information on what to write in ( )?

Question

C++ / C#

In general, very often I see in the codes of other people in ( ) they write either int / float, etc., that is, a certain condition or something. Is there any documentation on this at all? how do you understand what you can write there and when you need it?

Answer 1

Conversions of basic data types
Still
Have you blocked Google or something?