How to Add a Human Struct to Your Rust Program

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# How to Add a Human Struct to Your Rust Program

What the reader will be able to do: Define a `Human` struct with `name` and `age` fields and use it in a Rust program.

## Prerequisites
- Basic Rust program structure (from previous tutorial)
- Understanding of `fn main()` and `println!`

## Steps

1. **Define the Human struct**  
   Open `src/main.rs` and replace its contents with:
   ```rust
   struct Human {
       name: String,
       age: u32,
   }

   fn main() {
       let person = Human {
           name: String::from("Alice"),
           age: 30,
       };

       println!("Name: {}", person.name);
       println!("Age: {}", person.age);
   }
   ```

2. **Compile and run**  
   Run:
   ```bash
   cargo run
   ```
   Expected output:
   ```
   Name: Alice
   Age: 30
   ```

3. **Modify the struct fields**  
   Change the `name` and `age` values in `main()`:
   ```rust
   let person = Human {
       name: String::from("Bob"),
       age: 25,
   };
   ```
   Re-run `cargo run` to see the updated output.

## Pitfalls
- Forgetting to use `String::from()` for string literals (causes compilation errors)
- Using `i32` instead of `u32` for age (Rust requires unsigned integers for non-negative values)
- Not initializing struct fields in the correct order

## To go further
- Learn about Rust's `Option` and `Result` types for handling missing data
- Explore how to implement methods on structs using `impl` blocks