Why Does JavaScript\'s `new Date()` Show October When Given Month 9?

Discrepancy in Date Creation with JavaScript

In the provided JavaScript code snippet, a Date object is created with the following parameters:

var myDate = new Date(2012, 9, 23, 0,0,0,0);

However, upon logging the created myDate, it displays the month as October instead of September. This discrepancy arises due to the difference in month notation in JavaScript.

In JavaScript, the month parameter in the Date constructor represents the zero-based index of months, ranging from 0 to 11. Therefore, September, which is the ninth month, is represented by the index 8. This explains why the code snippet creates a Date object with a month value of 9, resulting in the display of October.

The reference for the Date constructor confirms this behavior:

new Date(year, month [, day, hour, minute, second, millisecond]);

Under the month parameter, it explicitly states:

Integer value representing the month, beginning with 0 for January to 11 for December.

Therefore, in JavaScript, when creating a Date object, it is crucial to remember that month indices begin from 0, making it necessary to subtract 1 from the month number to obtain the intended result.

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