function in Rust
A function definition specifies what and how a specific task would be done. A function must be called so as to execute it. This process is termed as function invocation. Functions may also return a value along with control, back to the caller. Parameters are a mechanism to pass values to functions. Parameters form a part of the function’s signature. /* fn main() { println!("Hello, world!"); another_function(); } fn another_function() { println!("Another function."); } */