This statement tells the browser to write "Hello Dolly." inside an HTML element with id="demo":
The statements are executed, one by one, in the same order as they are written.
In this example x, y, and z are given values, and finally z is displayed:
Add a semicolon at the end of each executable statement:
When separated by semicolons, multiple statements on one line are allowed:
On the web, you might see examples without semicolons. Ending statements with semicolon is not required, but highly recommended.
The following lines are equivalent:
A good practice is to put spaces around operators ( = + - * / ):
For best readability, programmers often like to avoid code lines longer than 80 characters.
The purpose of code blocks is to define statements to be executed together.
In this tutorial we use 4 spaces of indentation for code blocks. You will learn more about functions later in this tutorial.
Here is a list of some of the keywords you will learn about in this tutorial:
|break||Terminates a switch or a loop|
|continue||Jumps out of a loop and starts at the top|
|do ... while||Executes a block of statements, and repeats the block, while a condition is true|
|for||Marks a block of statements to be executed, as long as a condition is true|
|function||Declares a function|
|if ... else||Marks a block of statements to be executed, depending on a condition|
|return||Exits a function|
|switch||Marks a block of statements to be executed, depending on different cases|
|try ... catch||Implements error handling to a block of statements|
|var||Declares a variable|