Regular Expressions has two string methods: search() and replace(). The search() method uses an expression to search for a match, and returns the position of the match.
var msg = "Hello John";
var n = msg.search(/John/i); // 6
The replace() method is used to return a modified string where the pattern is replaced.
var msg = "Hello John";
var n = msg.replace(/John/i, "Buttler"); // Hello Buttler
