When calling the Date constructor it is possible to supply one or more arguments to the constructor that can be used to set the point in time in which the date object represents. When supplying two or more arguments like in the example above the first argument is a full year, and the second argument is a zero relative month of that year, followed by the day of the month and so forth. However there are many other options as well to set a date, more on that later.
When creating a Date object with a single argument if the single argument is a number that argument is treated as a number of milliseconds that has passed sense the first of January 1970, as the nature of unix time is based off that date in time.
When setting a value of zero the values that are received when using a Date prototype method such as todateString might not end up being what is expected. This is because of time zones, for example I am dealing with Eastern Standard Time where I live so there is a three hundred minute offset.
When setting from two or more arguments the first argument is the full year followed by the zero relative month of the year and then so on all the way to milliseconds.