1. Can you use x === "object" to test if x is an object?

In short, yes, but you must take into account the fact that null is considered an object in JavaScript. Even if x is null, 'console.log(typeof x === "object")' will log true instead of false.
To account for this, you must also test whether or not x is null by including the following:
console.log((x !== null) && (typeof x === "object"));

2. What happens when you don't declare a variable in Javascript?

If you don't explicitly declare a variable, you risk creating an implied global variable. This is a problem, as you will be unable to create multiple instances of that object, as each new instance will overwrite the data from the last.
In general, global variables should be used only in very specific situations and are typically not recommended, as they can lead to a lot of odd side effects that may be difficult to track down.

3. How can I prevent others from reading/stealing my scripts or images?

There are no assertive measures which can be taken to foolproof your scripts and images, but preventive measures can be taken like copyrighting your pages, putting watermark on your images and applying non-technological way to protect your images. Scripts are difficult to protect as they can be accessed through many applications and many programs by using the web browsers.

4. Explain the concept of unobtrusive JavaScript?

Unobtrusive JavaScript is basically a JavaScript methodology that seeks to overcome browser inconsistencies by separating page functionality from structure. The basic premise of unobtrusive JavaScript is that page functionality should be maintained even when JavaScript is unavailable on a user's browser.

5. What is the difference between script type and the script language attributes?

► The script type specifies the type of content that is used to show the language used by the browsers like "language=text/javascript". This defines the MIME type that is also known as Multipurpose Internet Mail Extensions (MIME). Text in this defines a plain text format and script defines the language that will be used.
► The script language attribute on the other hand specify a particular version of JavaScript language that is required to run the script and to provide a mechanism to fall back if any browser doesn't support it.
► Script type is used to define the type through which the browser can understand the language and all the compatible browsers can execute the type according to themselves, whereas the script language attribute defines the content and its attributes that are used.

6. What is namespacing in JavaScript and how is it used?

Namespacing is used for grouping the desired functions, variables etc. under a unique name. It is a name that has been attached to the desired functions, objects and properties. This improves modularity in the coding and enables code reuse.

7. What is NaN in JavaScript?

Nan is literally "Not-a-Number". NaN usually results when either the result or one of the values in an operation is non-numeric. Even though NaN is not a number, 'console.log(typeof NaN === "number");' logs true, while NaN compared to anything else (including NaN) logs false. The only real way to test if a value is equal to NaN is with the function 'isNaN()'.

8. What is unescape() function?

► The unescape() function is used to decode the encoded string.
► Syntax : unescape(string1)
► Where string1 is the string to be decoded.
► Example :
- Output :
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9. How are JavaScript and ECMA Script related?

ECMAScript is nothing but another name for JavaScript. Precisely, ECMAScript is the formal name of JavaScript, when XML elements have to be accessed.

10. Which boolean operators are in JavaScript?

'and' operator: &&
'or' operator: ||
'not' operator: !

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