What data type is props?

Could you please elaborate on the data type of the term "props" in the context of programming or software development? Specifically, I'm curious about how it's typically defined and used, and if there's a standard data type that it corresponds to. Is it a primitive type like a string or a number, or is it more complex, like an object or an array? Additionally, I'm interested in understanding how the concept of "props" relates to frameworks and libraries, such as React, and if there are any best practices or guidelines for using them effectively.