When using strings you can either use
str, which are static and cannot be
grown, or the more dynamic
String type, which can be appended, sliced and
increased because it's allocated on the heap.
&str- stack allocated fixed-size string slice. Used as fn arguments.
String- heap allocated growable string
let hello = String::from("Hello, world!"); // String from literal
string literal to string collection
Gathered from IRC:
"foo".into() // is a short way of getting a String
string to uppercase
&str.to_uppercase(); // String slice to uppercase