Question

I am for the most part a developer in ASP.NET and C#. I name my variables starting in lowercase and my methods starting in uppercase. but most javascript examples I study have functions starting in lowercase. Why is this and does it matter?

function someMethod() { alert('foo'); }

vs

function SomeMethod() { alert('bar'); }

Answer 1

A popular convention in Javascript is to only capitalize constructors (also often mistakenly called “classes”).

function Person(name) {
  this.name = name;
}
var person = new Person('John');

This convention is so popular that Crockford even included it in its JSLint under an optional — “Require Initial Caps for constructors” : )

Anything that’s not a constructor usually starts with lowercase and is camelCased. This style is somewhat native to Javascript; ECMAScript, for example (ECMA-262, 3rd and 5th editions) — which JavaScript and other implementations conform to — follows exactly this convention, naming built-in methods in camelcase — Date.prototype.getFullYear, Object.prototype.hasOwnProperty, String.prototype.charCodeAt, etc.