add String type

variables/src/main.rs

@@ -11,6 +11,10 @@ fn main() {
     let height: f64 = 1.79;
     let character: char = 'M';
     let has_driver_license: bool = true;
+    let mut text = "Hello".to_string();
+    text.push_str(" World");
+    let text2 = String::from("Hello world2");
+    println!("{} {}",text,text2);
 
     //make them mutable by mut modifier
     let mut middle_name = "Levy";