JavaScript 64- IEEE 754 (.. , -(253 -1) 253 -1). . , : +, -, NaN (-). JavaScript JavaScript.

: , , .

1234567890;
42;

//        :

0888; // 888   
0777; //       (511  )

, (0) , 8, .

0 "B" (0b or 0B). 0b 0 1, SyntaxError : "Missing binary digits after 0b".

var FLT_SIGNBIT = 0b10000000000000000000000000000000; // 2147483648
var FLT_EXPONENT = 0b01111111100000000000000000000000; // 2139095040
var FLT_MANTISSA = 0b00000000011111111111111111111111; // 8388607

. 0 0 7, .

var n = 0755; // 493
var m = 0644; // 420

0 "X" (0x or 0X). 0x (0123456789ABCDEF), SyntaxError : "Identifier starts immediately after numeric literal".

0xfffffffffffffffff; // 295147905179352830000
0x123456789abcdef; // 81985529216486900
0xa; // 10

Number

Number , , - . , :

var biggestNum = Number.MAX_VALUE;
var smallestNum = Number.MIN_VALUE;
var infiniteNum = Number.POSITIVE_INFINITY;
var negInfiniteNum = Number.NEGATIVE_INFINITY;
var notANum = Number.NaN;

, , Number. , , .

Number.

Number , . , Number.prototype.

Math

Math . , Math PI "" (3.141...),

Math.PI;

, Math. , , . , ,

Math.sin(1.56);

, Math .

Math.

, Math. Math .

Date

JavaScript . , Date . Date , , .

JavaScript Java. , , 00:00:00 1 1970 .

, Data, -100 000 000 100 000 000 , 1 1970 .

Date :

var dateObjectName = new Date([parameters]);

dateObjectName , Date; , , .

Date , new, .

parameters , :

• : . : today = new Date();.
• , : " , ::". : var Xmas95 = new Date("December 25, 1995 13:30:00"). , , 0.
• , . : var Xmas95 = new Date(1995, 11, 25).
• , , , , . : var Xmas95 = new Date(1995, 11, 25, 9, 30, 0);.

new Date().toLocaleString('ru',
  {
    day: 'numeric',
    month: 'long',
    year: 'numeric'
  });
//    : '10  2019 .'

toLocalString

Date

Date :

• "set" , Date.
• "get" , Date.
• "to" , Date .
• "parse" UTC , .

"get" "set", , , , , , . getDay, , setDay , - . :

• : 0 59
• : 0 23
• : 0 () 6 ()
• : 1 31
• : 0 () 11 ()
• : 1900 .

, , :

var Xmas95 = new Date("December 25, 1995");

Xmas95.getMonth() 11, Xmas95.getFullYear() 1995.

getTime setTime . getTime , 00:00:00 1 , 1970 .

, :

var today = new Date(); //   
var endYear = new Date(1995, 11, 31, 23, 59, 59, 999); //       
endYear.setFullYear(today.getFullYear()); //   
var msPerDay = 24 * 60 * 60 * 1000; //     
var daysLeft = (endYear.getTime() - today.getTime()) / msPerDay;
var daysLeft = Math.round(daysLeft); //   ,    

Date today, . , Date , endYear, , . , , today endYear, getTime , .

parse Date . , parse setTime IPOdate:

var IPOdate = new Date();
IPOdate.setTime(Date.parse("Aug 9, 1995"));

JSClock(), :

function JSClock() {
  var time = new Date();
  var hour = time.getHours();
  var minute = time.getMinutes();
  var second = time.getSeconds();
  var temp = "" + (hour > 12 ? hour - 12 : hour);
  if (hour == 0) temp = "12";
  temp += (minute < 10 ? ":0" : ":") + minute;
  temp += (second < 10 ? ":0" : ":") + second;
  temp += hour >= 12 ? " P.M." : " A.M.";
  return temp;
}

, JSClock Date, time; , time . getHours, getMinutes getSeconds, hour, minute second.

time. temp, ; hour 12, (hour - 12), hour. , hour 0, "12".

temp. 10, , , . temp .

, "P.M." temp hour 12, , "A.M.".