Basic Level Interview Questions
Here are some frequently asked questions in the interview.
var is function-scoped and can be re-declared and updated, while let and const are block-scoped and cannot be re-declared but can be updated (in the case of let) or cannot be updated (in the case of const).
== is a loose equality comparison operator that checks if two values are equal, while === is a strict equality comparison operator that checks if two values are equal in value and data type.
A method is a property of an object that is a function, whereas a function can be a standalone or a property of an object.
Synchronous programming blocks the execution of code until a task is completed, while asynchronous programming allows the code to continue executing while a task is being completed in the background.
Callbacks are functions passed as arguments to another function to be executed when a task is complete, while Promises are objects representing the eventual completion (or failure) of an asynchronous operation, and can be used to handle success and error conditions.
let and const are both block-scoped, but let can be reassigned a new value, while const cannot be reassigned once it has been assigned a value.
- What do you mean by currying?
Both call and apply methods are used to invoke a function with a specific value of this and arguments are passed as an array (apply) or comma-separated list (call), but the difference is in how the arguments are passed.
The slice method returns a shallow copy of a section of an array, whereas the splice method modifies the content of an array by deleting and/or adding components.
Classical inheritance is a way of creating classes and objects based on a hierarchical class structure, while prototypal inheritance is a way of creating objects by inheriting them directly from other objects.
Advanced Level Interview Questions
By attaching an event listener to a parent element rather than each individual child element, you may use the concept of event delegation. By doing so, you can handle events more effectively and use fewer event listeners across your code.
A pure function is a function that always returns the same output for a given input, and has no side effects outside of the function. This makes them easier to test and reason about and reduces the likelihood of bugs in your code.
The call, apply, and bind methods are used to manipulate the context of a function, allowing you to specify the value of the “this” keyword and pass arguments to the function. The main difference between them is the way in which arguments are passed to the function.
A web worker is a background thread of execution that allows you to offload CPU-intensive activities off the main thread. This can improve your program’s responsiveness and prevent the UI from freezing while long-running activities are executed.
You may delegate CPU-intensive activities from the main thread to a web worker, a second thread of operation that runs in the background. This can make your software more responsive and stop the UI from stalling while lengthy processes are finished.
Contrarily, asynchronous I/O permits other code to continue running while the I/O operation is ongoing, which can enhance an application’s performance and responsiveness.
Brush up on Key Concepts and Principles
Practice Coding Problems and Challenges
There are many resources available online to help you practise coding problems and challenges, which will help you build your skills and improve your ability to solve complex problems in real time during the interview.
Prepare for Behavioural Questions
In addition to technical questions, many interviewers will also ask behavioural questions to assess your communication and collaboration skills. Be prepared to answer questions about your work experience, team projects, and problem-solving approach.
Keep Cool and Confident Throughout the Interview Process
Be calm and confident during the interview process, especially if you are asked a challenging question. Take a deep breath, relax, and don’t be hesitant to ask for clarification if necessary.
Follow up after the Interview
After the interview, send a thank you email or letter to your interviewer, expressing your excitement for the opportunity to join their team.
Common Mistakes to Avoid During the Interview Process
Not Grasping the Fundamentals
Not Coding on a Frequent Basis
Overemphasis on Syntax
Not Asking Clarifying Questions
If you don’t understand a question or need clarification, don’t be hesitant to ask for more information from the interviewer.
Not Discussing Your Thought Process
As you work through a problem, explain your thought process to the interviewer. This will demonstrate your problem-solving skills and allow the interviewer to better understand your approach.
Not Testing Your Code
Before submitting your solution, test it thoroughly to ensure that it works correctly and efficiently.
Not Demonstrating Your Knowledge of Best Practices
Show the interviewer that you are familiar with best practices, such as using descriptive variable names, commenting on your code, and organising your code into reusable functions.
Not Showing Enthusiasm
What can a software developer earn?