10+ Interview Questions and Answers

Choose database based on project requirements, scalability, performance, and budget.

• Consider the type of data you will be storing (structured, unstructured, semi-structured)

• Evaluate the scalability requirements of your project

• Assess the performance needs of your application

• Take into account the budget constraints for the project

• Consider the level of expertise available for managing the database

• Examples: MySQL for small-scale projects, MongoDB for unstructured data, PostgreSQL...read more

CSS specificity determines which style rule is applied to an element when multiple rules have conflicting selectors.

• Specificity is calculated based on the type of selector used in a CSS rule.

• Inline styles have the highest specificity, followed by IDs, classes, and elements.

• Using !important in a rule increases its specificity, but should be used sparingly.

• Specificity is important to understand when troubleshooting CSS styling issues.

Normal functions are defined using the function keyword, while arrow functions are defined using the => syntax.

• Normal functions are hoisted, while arrow functions are not.

• Arrow functions do not have their own 'this' keyword, they inherit it from the parent scope.

• Arrow functions are more concise and have implicit return.

• Arrow functions cannot be used as constructors.

• Example: const normalFunction = function() {}; const arrowFunction = () => {};

Docker is a platform for developing, shipping, and running applications using containerization technology.

• Docker is used to create, deploy, and run applications in containers.

• Some common Docker commands include 'docker run' to run a container, 'docker build' to build an image, and 'docker push' to push an image to a registry.

• Docker containers are lightweight, portable, and isolated environments that package an application and its dependencies.

• Docker images are read-only templ...read more

Closure in JavaScript is the combination of a function and the lexical environment within which that function was declared.

• Closure allows a function to access variables from its outer scope even after the outer function has finished executing.

• It is created whenever a function is defined within another function, and the inner function has access to the outer function's variables.

• Example: function outerFunction() { let outerVar = 'I am outer'; function innerFunction() { console...read more

Docker is useful for containerization, allowing for easy deployment and scaling of applications.

• Docker allows for consistent environments across development, testing, and production.

• It improves efficiency by reducing the time and effort needed to set up and configure environments.

• Containers can be easily moved between different hosts, making deployment and scaling simpler.

• Docker enables microservices architecture, breaking down applications into smaller, manageable components...read more

React state management is a way to manage and update the state of components in a React application.

• State management helps in storing and updating data within components.

• React provides built-in state management using the useState hook.

• For more complex state management, libraries like Redux or Context API can be used.

• State management helps in keeping the UI in sync with the data changes.

Docker is a platform for developing, shipping, and running applications in containers.

• Docker allows developers to package applications and their dependencies into containers.

• Containers are lightweight, portable, and isolated environments that can run on any system.

• Docker simplifies the process of building, deploying, and scaling applications.

• Example: Running a web server in a Docker container.

Callback is a function that is passed as an argument to another function and is executed after the completion of that function.

• Callback functions are commonly used in asynchronous programming to handle tasks that take time to complete.

• Examples include event listeners in web development, setTimeout function in JavaScript, and AJAX requests.

• Callbacks can be synchronous or asynchronous depending on the programming language and context.

Closures are functions that have access to variables from their containing scope even after the function has finished executing.

• Closures allow functions to 'remember' variables from their outer scope

• They are commonly used in event handlers and callbacks

• Closures help in creating private variables in JavaScript

Closure in JavaScript allows a function to access variables from its outer scope even after the outer function has finished executing.

• Closure is created when a function is defined within another function and has access to the outer function's variables.

• The inner function can access and modify the outer function's variables even after the outer function has returned.

• Closure is commonly used to create private variables and functions in JavaScript.

• Example: function outerFunction...read more