Error messages

When your script encounters an error, an error message is displayed in a red bar at the top of the screen. The message is accompanied by a line number used for troubleshooting. There are two basic types of errors displayed in this way: syntax errors and runtime errors.

Syntax Errors:

Syntax errors are caused by writing code that doesn't follow the JavaScript grammar, and the errors are detected as soon as you try to save the script. The following code snippet contains a syntax error:

function syntaxError()
{
	

Error messages

When your script encounters an error, an error message is displayed in a red bar at the top of the screen. The message is accompanied by a line number used for troubleshooting. There are two basic types of errors displayed in this way: syntax errors and runtime errors.

Syntax errors

Syntax errors are caused by writing code that doesn't follow the JavaScript grammar, and the errors are detected as soon as you try to save the script. 

Runtime errors

These errors are caused by using a function or class incorrectly, and can only be detected once the script has been run.