onclick or onClick?

Question

I thought that binding the click event in javascript is done by using node.onclick, and Chrome/Firefox seem to agree with me, but I saw it written .onClick here 4 times by 3 people, so it can't be a typo and I doubt that it's a coincidence.

So, why are people writing onClick when it does not work?

UPDATE: There are two good explanations; I don't know which one of them is the most plausible, so I will accept the answer based on popular vote, tomorrow.

Answer 1

Because some browsers (depending on the DOCTYPE) are tolerant of the inline onClick="something();" attribute...it seems to have spread a bit, even into JavaScript questions where it doesn't work, since case matters.

Also, specifically to stackoverflow...people using it in questions...well, most of the time they wouldn't be asking a question if their code worked :)

Answer 2

@Nick Craver pretty much has it nailed down and has my vote; I just wanted to add my thought.

I think it's onClick is often used in conversation because it's a bit more readable, and as an old habit from those of us who predate all lowercase HTML. However, in code - both JavaScript and HTML, onclick is correct and the only way it should appear. Even if you're using an older HTML doctype, stick to lowercase. If you ever update to a more strict doctype, you'll be glad your code doesn't need to be checked for case.