generate aleatory code js

1function makeid(length) {
2    var result           = [];
3    var characters       = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
4    var charactersLength = characters.length;
5    for ( var i = 0; i < length; i++ ) {
6      result.push(characters.charAt(Math.floor(Math.random() * 
7 charactersLength)));
8   }
9   return result.join('');
10}
11
12console.log(makeid(5));