JavaScript Basic Rules

// 1. JavaScript is case-sensitive

/*
var myTest = "I am Thet Naing Win";
var mytest = "Who are you?"
document.write(mytest);
*/

// 2. All the statements should end in semicolon
/*
var myStatement1 = "I am Thet Naing Win.";
var myStatement2 = "I am from Myanmar.";
var myStatement3 = "I live in Yangon now.";
var myStatement4 = "I am 35 now.";
document.write(myStatement1 + " " + myStatement2 + " " + myStatement3 + " " + myStatement4);
*/

// 3. All the variables mu be defined before using it. The type of data is put into the variables.
/*
var myVar1 = "I am Thet Naing Win."; //String
var myVar2 = "I am 35 now."; //number
document.write(myVar1 + " " + myVar2);
*/

// Global variable and local variable

/*
var tnwGlobal = "I am TNW Global."; //global variable

function myFun1(){
    var tnwLocal1 = "I am TNW Local one."; //local variable
    document.write(tnwGlobal + "<br />" + tnwLocal1);
}

function myFun2(){
    var tnwLocal2 = "I am TNW Local two."; //local variable
    document.write(tnwGlobal + "<br />" + tnwLocal2 + "<br />" + tnwLocal1);
}
*/
//Function two does not work as the local variable from myFun1() is being used in myFun2().

// 4. We can use single quotation mark or double quotation mark to declare the strings
/*
var myString1 = "I am Thet Naing Win.";//double quotation mark
var myString2 = 'I am from Myanmar.';//single quotation mark
document.write(myString1 + "<br />" + myString2);
*/

// 5. Varialbe increment or decrement
/*
var a;
a = a + 1; //or
a++;

a = a - 1; //or
a--;
*/
// For example
/*
for(var a = 9; a >= 1; a--){
    document.write(a + "<br />");
}
*/

// 6. Comments
// We can use // or /* ------- */