Many JavaScripts deal with variables. This is where you take a word or letter and assign a value to it. The value can be either numbers or words. To think of it in physical terms, imagine a box with a label stuck on it and there is a piece of paper with a name or number written on it inside the box. The labeled box is a variable, and the name or number on the paper is the value.

<Code
  language="javascript"
  text={`var Z = X + Y`}
/>

Look horribly familiar? It's the stuff you learn in school and think to yourself "When will I EVER need to know algebra in real life ?". Well... here it is.

You can use strings (regular text) instead of numbers in these equations too. Or a number and a string.

<Code
  language="javascript"
  text={`"This is " + "HTMlite." = This is HTMlite.
"HTMlite " + 99	= HTMlite 99`}
/>

Other than the usual assignment operators **+ - / * =** you can use JavaScript to compare two or more variables with each other. That is, it takes two values and compares them to each other. Here is a list of the different types of comparisons there are:

<Code
  language="javascript"
  text={`X == Y // True if X and Y are equal.
X != Y // True if X and Y are not equal.
X > Y // True if X is greater than Y.
X >= Y // True if X is greater than or equal to Y.
X < Y // True if X is less than Y.
X <= Y // True if X is less than or equal to Y.
X && Y // True if X and Y are true values.
X || Y // True if X or Y have a true value.
!X // True if X has a false value.`}
/>

As stated before, part of having a numeric value in variables lets you use regular math expressions on them like so...
<Code
  language="javascript"
  text={`X += Y // X = X + Y
X -= Y // X = X - Y
X *= Y // X = X * Y
X /= Y // X = X / Y
X %= Y // X = X % Y`}
/>

Learn how to "save" results of function in JavaScript variables.

JavaScript Variables

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