Why is `setTimeout(alertMsg, 3000)` preferred over `setTimeout('alertMsg()', 3000)`?

Differences between Using setTimeout with Quotes and Parentheses

When using setTimeout, you can call the function directly without quotes or parentheses, or you can wrap the function name in quotes with parentheses. Here's the breakdown:

With Parentheses:

setTimeout("alertMsg()", 3000);

In this case, "alertMsg()" is treated as a string, and setTimeout will execute this string as a script. This approach is not recommended as it can lead to unexpected behavior.

Without Quotes and Parentheses:

setTimeout(alertMsg, 3000);

This is the preferred way to pass a function reference to setTimeout. It directly passes alertMsg, which is assumed to be a function.

With Quotes Only:

setTimeout("alertMsg", 3000);

This is an alias for the previous example, but it's not recommended. It implies that you're passing a string to setTimeout, which can be misleading.

Additional Considerations for setTimeout

• Pass function reference: Always pass a function reference or anonymous function as the first argument to setTimeout.
• Pass arguments: To pass arguments to the function, use a callback or the less cross-browser compatible method of including them as arguments to setTimeout.
• Callback context: By default, the context of the callback is the global object window. You can change it using bind.
• Security: Avoid passing strings to setTimeout as it can execute arbitrary scripts.

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