weekDays = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];
monthes = ["January", "February", "March", "April", "May", "June",
"July", "August", "September", "October", "November", "December"];
var date = new Date();
var cday = date.getDay();
// The function getDay return a number
document.getElementById("cday").innerHTML += weekDays[cday];
// The current date
var cdate = date.getDate();
document.getElementById("cdate").innerHTML += cdate;
// Current month
var cmonth = date.getMonth();
// The function getMonth return the rank of the month
document.getElementById("cmonth").innerHTML += monthes[cmonth];
// Current year
var year = date.getFullYear();
document.getElementById("cyear").innerHTML += year;
// first day of a month
// first day of June 2020
// year month date
var fday = new Date(2020, 5, 1).getDay();
document.getElementById("fday").innerHTML += weekDays[fday];
// Numbers of days of a month
// Year month date (0 is the date before the selected month)
// 7 is august, 0 gives the last day of july
var numdays = new Date(2020, 7, 0).getDate();
document.getElementById("numdays").innerHTML += numdays;