Why is January 0 in Javascript date object while year, day, hour, ... starts to 1? [duplicate]

Question

Possible Duplicate:
Zero-based month numbering

Why is January month 0 in JS date object ? For instance, I would expect this snippet to create a date oject for the 8th of Februray 2013. Instead, it's March. All other fields areintuitive. Years are natural as well as day of month and time.

test_date = New Date(2013, 2, 8);

Is there any rational behind this ?

Answer 1

Because then you can have:

var monthnames = ["Jan","Feb","Mar"....];

And access the array by:

monthnames[myDate.getMonths()]

Similarly for weekdays, where Sunday is 0.

However, years, and days are just numeric values, not indices to some greater meaning.

Side-note: Hours, minutes and seconds are zero-based in "human time" too.