Date

The Date object allows you to create dates and access values such as year, month, day, and second.
If no argument is specified, it is initialized to the current date and time of the system.

var now = new Date();
alert("Now : " + now.toUTCString());

var milliSecs = new Date(7789110879);
alert("MilliSecs: " + milliSecs.toUTCString());

var soccerDay = new Date("June 14, 2018 16:00:00");
alert("Kick Off: " + soccerDay.toUTCString());

var birthday = new Date(1981,1,25);
alert("Birthday: " + birthday.toLocaleString());

var newYearsEve = new Date(2018,11,31,23,59,59,59);
alert("New Year's Eve: " + newYearsEve.toUTCString());
References