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5 interview questions that a JavaScript developer should know

5 interview questions that a JavaScript developer should know

In every company, especially IT companies, managers trust and give developers technical interviews to evaluate candidates. So, here are 5 interview questions that every JavaScript developer should know if you are the one assigned to this task.

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Can you name two programming models important to JavaScript application developers?

This is a great first question for candidates, it both assess the understanding and see the experience of the interviewer. Because JavaScript is a multi-paradigm language, it supports programming commands or procedures along with object and functional programming. JavaScript supports OOP with prototype inheritance. Candidates need to mention genetic prototype and functional programming.

What is functional programming?

Following the first question, a second question arises, that is, do you know: What is functional programming? This is also a very basic question and once you have answered the first question, the explanation for the above question is very easy. Therefore, it is easier to evaluate candidates from the outset to know if they know the functional information needed.

The request in the candidate's answer must mention: pure functionality, avoiding side effects, simple functional components ... In addition, there should be a few examples of functional languages ​​such as: Lips, ML, Haskell, Erlang ... and need to mention EP support functions such as: first-class functions, higher-order functions, argument functions ...

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What is the difference between classical inheritance and prototype inheritance?

To answer this interview question, candidates need to explain what is classical inheritance and what is archetypal inheritance. It is more important to compare these two types of inheritance and to know what kind of inheritance should be used. Candidates will be skipped if not mention that prototype inheritance should take precedence over classic inheritance. So, this will be one of the questions employers should not overlook during interviewing candidates at their companies.

What are the pros and cons of functional programming versus object-oriented programming?

Advantages need to mention basic concepts that are relatively easy to understand and easy to explain the meaning of the methods. OOP tends to use a mandatory type instead of a declarative type, it reads like a simple set of instructions that computer types can easily follow.


On the downside of OOP, usually depends on the state of sharing. OOP objects and behaviors are addressed on the same, randomly accessible entity. Applicants must mention the above information to answer the question.

When is classical inheritance an appropriate option?

The most accurate answer to the above question is never and almost never. Applicants should answer that and reaffirm the use of prototype inheritance. The plus point for candidates is to speak out about the limitations of classical inheritance in this answer.

The above are 5 interview questions every JavaScript developer should know, these questions will help partly assess the competencies of the candidates as well as check the general level of knowledge that will hopefully help the students. employers during the interview process. The interview questions are very important if you want to recruit qualified candidates and ensure the quality of the job in the future.

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