{"resource":{"author":{"id":"3eh0kijZwMrHum8TkMqX","name":"Devtools Tech","username":"devtoolstech"},"content":{"link":null,"difficulty":1,"domain":2,"type":1,"isInternal":true,"body":"[JavaScript](https://devtools.tech/questions/all?searchTerm=javascript&language=javascript), created by Brendan Eich in 1995, is one of the most widely used web development languages. It was designed to build dynamic web pages at first. A script is a JS program that may be added to the HTML of any web page. When the page loads, these scripts execute automatically.\r\n\r\nA language that was originally designed to build dynamic web pages may now be run on the server and on almost any device that has the JavaScript Engine installed.\r\n\r\nAfter [HTML](https://devtools.tech/questions/all?searchTerm=html&language=html) and [CSS](https://devtools.tech/questions/all?searchTerm=css), JavaScript is the third biggest web technology. JavaScript is a scripting language that may be used to construct online and mobile apps, web servers, games, and more. JavaScript is an object-oriented programming language that is used to generate websites and applications. It was created with the intention of being used in a browser. Even today, the server-side version of JavaScript known as Node.js may be used to create online and mobile apps, real-time applications, online streaming applications, and video games. Javascript frameworks, often known as inbuilt libraries, may be used to construct desktop and mobile programs. Developers may save a lot of time on monotonous programming jobs by using these code libraries, allowing them to focus on the production work of development.\r\n\r\nThe Devtools Tech team has compiled a thorough collection of top **Javascript Interview Questions** based on **Array Polyfills** and answers to assist you in acing your interview and landing your desired job as a Javascript Developer.\r\n\r\n## JavaScript Interview Questions Based on Array Polyfills \r\n\r\n1. [How to flatten a deeply nested array?](https://devtools.tech/questions/s/how-to-create-a-flat-version-of-a-deeply-nested-array-programming-interview-question---qid---l5Qx4LJ7glelCkIxQjXB?listId=bzcbM8FDmAP0tCcJhKfe)\r\n2. [How to implement Array indexOf method?](https://devtools.tech/questions/s/how-to-implement-array-indexof-from-scratch-or-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---uiKZDYRDupbHmsdteY4i?listId=bzcbM8FDmAP0tCcJhKfe)\r\n3. [How to implement Array includes method?](https://devtools.tech/questions/s/how-to-implement-array-prototype-includes-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---w4dQTfaSXWAm6UOowema?listId=bzcbM8FDmAP0tCcJhKfe)\r\n4. [How to implement Array findIndex method?](https://devtools.tech/questions/s/how-to-implement-arrayprototypefindindex-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---DWM4ApioOxMMCYuHoe9I?listId=bzcbM8FDmAP0tCcJhKfe)\r\n5. [How to implement Array find method?](https://devtools.tech/questions/s/how-to-implement-array-prototype-find-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---nX72m7o44hxRUlSnbjo5?listId=bzcbM8FDmAP0tCcJhKfe)\r\n6. [How to implement Array at method?](https://devtools.tech/questions/s/how-to-implement-array-prototype-at-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---cbVcZ8jIXITU5wD6hIrb?listId=bzcbM8FDmAP0tCcJhKfe)\r\n7. [How to implement Array some method?](https://devtools.tech/questions/s/how-to-implement-array-prototype-some-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---gjENt0b0pXZYASeLYQFS?listId=bzcbM8FDmAP0tCcJhKfe)\r\n8. [How to implement Array every method?](https://devtools.tech/questions/s/how-to-implement-array-prototype-every-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---z73LTBqI8n43iyjzmPu7?listId=bzcbM8FDmAP0tCcJhKfe)\r\n9. [How to implement Array unshift method?](https://devtools.tech/questions/s/how-to-implement-array-prototype-unshift-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---whZsVI7ihgobZxBaW0Jm?listId=bzcbM8FDmAP0tCcJhKfe)\r\n10. [How to implement Array pop method?](https://devtools.tech/questions/s/how-to-implement-array-prototype-pop-javascript-interview-question-or-problem-solving-or-javascript-polyfills---qid---lujToJoIqX1KHvWPiqQf?listId=bzcbM8FDmAP0tCcJhKfe)\r\n\r\nThe full list could be found here: [Top JavaScript Array Interview Questions | Problem Solving | Array Polyfills](https://devtools.tech/lists/s/top-javascript-array-interview-questions-or-problem-solving-or-array-polyfills---lid---bzcbM8FDmAP0tCcJhKfe)\r\n\r\n## Recommended Resources\r\n\r\n- [How to improve your codebase using Custom ESLint Rules | Advanced JavaScript](https://devtools.tech/resources/s/how-to-improve-your-codebase-or-custom-eslint-rules-or-advanced-javascript-or-devtools-tech---rid---KgSipm8RngCFwwtI7bh2)\r\n- [Build Your Own Redux | Part 1](https://devtools.tech/resources/s/build-your-own-redux-or-part-1-or-advanced-frontend---rid---MNkFAzvLnmds66wD3JV0)\r\n- [Build Your Own Redux | Part 2](https://devtools.tech/resources/s/create-your-own-redux-or-part-2-or-createstore-api-or-advanced-frontend---rid---H9EEn90tE3Jag6zCfNkM)\r\n- [Things Every Engineer Should Know About Promises | JavaScript Fundamentals | Part 1](https://devtools.tech/resources/s/things-every-engineer-should-know-about-promises-in-javascript-or-frontend-fundamentals---rid---CpzShsPEajyOwTavUu5O)\r\n- [Things Every Engineer Should Know About Promises | JavaScript Fundamentals | Part 2](https://devtools.tech/resources/s/javascript-promises-fundamentals-every-engineer-should-know-or-part-2-or-event-loop-or-microtasks---rid---oBrzK6Mt7HNAnKBT3ogC)\r\n\r\n## Recommended Lists\r\n\r\n- [Advanced JavaScript Interview Questions](https://devtools.tech/lists/s/advanced-javascript-interview-questions-or-problem-solving-or-frontend-interview-questions---lid---OpoqiRpqSIrBL1nuonZ0)\r\n- [DevKode DOM Coding Challenges](https://devtools.tech/lists/s/frontend-coding-challenges-or-javascript-or-reactjs-or-devkode-dom-challenge---lid---6mVGooqtFwIY9rhHKSug)\r\n- [Top JavaScript Promises Interview Questions | Promise Polyfills](https://devtools.tech/lists/s/top-javascript-promises-interview-questions-or-problem-solving-or-promise-polyfills---lid---2ei6fSnqpupoMQFt6Zvj)","languages":[],"editorConfig":{}},"stats":{"views":19758,"used":0,"likes":0},"description":"","published":true,"isActive":true,"tags":["javascript","frontend","code","array","interview questions","array polyfills","advanced javascript","js interview questions","hackerrank","codedamn","coding","interview preparation"],"slug":"top-10-javascript-interview-questions-based-on-array-polyfills---rid---oNzRUjONl4YB5ixIEGrl","isPremium":false,"categories":[],"requires":[],"_id":"636cd77320622762d08cfe22","title":"Top 10 JavaScript Interview Questions based on Array Polyfills","resourceId":"oNzRUjONl4YB5ixIEGrl","createdAt":1668077427823,"modifiedAt":1668244107214},"currentUser":null,"isOwner":false,"recommendations":{"questions":[{"_id":"69d242fda18a6decde9626ad","content":{"languages":["javascript"],"difficulty":1},"tags":["javascript","ui","ux","code tooling","output","frontend","coding","output based questions","interview challenge"],"slug":"can-you-predict-the-answer-this-keyword---qid---BfcD5gdHrq3qCG3q1Znx","title":"Can you predict the answer? 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