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In JavaScript and browser based programming, which of the following best describes the main built in objects that are commonly used?

Difficulty: Easy

Correct Answer: Core language objects such as Object, Array, String, Date, Math, and browser objects such as window, document, location, navigator, and history.

Explanation:


Introduction / Context:

JavaScript provides many built in objects that form the foundation for working with data, time, and the browser environment. Understanding the main categories of these objects helps developers quickly recognize what tools are available for common tasks such as list manipulation, string operations, dates, and interaction with the web page and browser.


Given Data / Assumptions:

  • We focus on standard JavaScript environments in web browsers.
  • JavaScript has core language objects that are independent of the browser.
  • Browsers add additional host objects that allow scripts to interact with windows and documents.


Concept / Approach:

The JavaScript language itself defines core objects such as Object, Array, Function, String, Number, Boolean, Date, RegExp, and Math. These provide the basic data structures and utilities needed in any JavaScript program. When running in a browser, JavaScript code also interacts with host objects supplied by the environment, including window (the global object for the browser window), document (the DOM tree representing the page), location (the current URL), navigator (information about the browser), and history (the session history stack). Together, these objects form the main toolkit used in client side web programming.


Step-by-Step Solution:

Step 1: Identify the standard core language objects: Object, Array, String, Date, Math, and others. Step 2: Identify the primary browser host objects: window, document, location, navigator, and history. Step 3: Recognize that these objects appear in almost every example of client side JavaScript. Step 4: Compare the options and select the one that lists both core and browser objects correctly. Step 5: Confirm that no option mentioning hardware or database objects matches the reality of the JavaScript environment.


Verification / Alternative check:

Opening the browser console and typing Object, Array, window, and document shows that these names refer to built in constructors or objects. Documentation on MDN and other references lists these same objects under JavaScript standard built ins and Web APIs, confirming they are the main objects used in practice.


Why Other Options Are Wrong:

Option B is wrong because there is no single global object named main that contains all code and data; window plays the role of the global object in browsers. Option C is wrong because JavaScript does not directly expose low level hardware objects like CPU or Disk; access is abstracted and restricted for security. Option D is wrong because database objects such as Table and Trigger are not built in browser objects; databases are accessed through APIs, not as native JavaScript objects. Option E is wrong because JavaScript has many built in objects beyond DOM elements, including its core language types.


Common Pitfalls:

Beginners sometimes think only DOM elements matter in JavaScript and overlook powerful core objects like Array and Date. Another pitfall is assuming that anything available in a server side language is also directly available in JavaScript, which is not true; browser security and sandboxing restrict access to hardware and local resources.


Final Answer:

The correct choice is Core language objects such as Object, Array, String, Date, Math, and browser objects such as window, document, location, navigator, and history. because this option accurately describes the main categories of objects commonly used in JavaScript web development.

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