diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..d95b684
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,47 @@
+#![allow(dead_code)]
+
+struct Person {
+    age: i32,
+    name: String,
+}
+
+impl ToString for Person {
+    fn to_string(&self) -> String {
+        format!("{} ({})", self.name, self.age)
+    }
+}
+
+fn greet_person_1(p: Person) {
+    println!("Hello {} ({})!", p.name, p.age);
+}
+
+fn greet_person_2(p: &Person) {
+    println!("Hello {} ({})!", p.name, p.age);
+}
+
+fn birthday(p: &mut Person) {
+    p.age += 1;
+}
+
+fn main() {
+    // -- Struct instantiation --
+    let mut p = Person { age: 30, name: "Mary".to_string() };
+
+    // -- Borrowing --
+    //greet_person_1(p);
+    //greet_person_1(p);
+
+    greet_person_2(&p);
+    greet_person_2(&p);
+
+    birthday(&mut p);
+
+    greet_person_2(&p);
+
+    // -- Traits --
+    println!("p = {}", p.to_string());
+
+    // -- Debugging --
+    let x = dbg!(100 + 2) + 3;
+    println!("Hello, world!  100 + 2 + 3 = {}", x);
+}