fix typo

README.md

@@ -892,7 +892,7 @@ fn main() {
 That will print `[73, 32, 108, 105, 107, 101, 32, 116, 111, 32, 119, 114, 105, 116, 101, 32, 34, 35, 34, 46]`.
 
 
-There is also a Unicode escape that lets you print any Unicode character inside a string: `\u{}`. A hexidecimal number goes inside the `{}` to print it. Here is a short example of how to get the Unicode number, and how to print it again.
+There is also a Unicode escape that lets you print any Unicode character inside a string: `\u{}`. A hexadecimal number goes inside the `{}` to print it. Here is a short example of how to get the Unicode number, and how to print it again.
 
 ```rust
 fn main() {