40+ Senior Web Developer Interview Questions and Answers

Polymorphism is the ability of a function or method to behave differently based on the object it is acting upon.

• Polymorphism allows objects of different classes to be treated as objects of a common superclass.

• It enables a single interface to represent a group of related interfaces.

• Examples include method overloading and method overriding in object-oriented programming.

Using JavaScript to add functionality to a web page design

• Use event listeners to trigger actions based on user interactions

• Manipulate the DOM to update content dynamically

• Utilize AJAX to fetch data from a server without refreshing the page

The main part of hacking is gaining unauthorized access to a system or network.

• Hacking involves exploiting vulnerabilities in software or hardware

• It can be used for malicious purposes such as stealing data or disrupting services

• Ethical hacking is a legitimate practice used to identify and fix security weaknesses

• Examples of hacking techniques include phishing, SQL injection, and social engineering

SQL queries can extract and summarize data from tables to generate insightful reports for analysis and decision-making.

• SELECT Statement: Use SELECT to specify columns to retrieve, e.g., SELECT name, age FROM users;

• JOIN Operations: Combine data from multiple tables, e.g., SELECT orders.id, users.name FROM orders JOIN users ON orders.user_id = users.id;

• GROUP BY Clause: Aggregate data, e.g., SELECT COUNT(*), status FROM orders GROUP BY status;

• WHERE Clause: Filter results based o...read more

Microservices are a software development technique where applications are composed of small, independent services that communicate with each other through APIs.

• Microservices break down a large application into smaller, manageable services

• Each service is responsible for a specific function and can be developed, deployed, and scaled independently

• Communication between services is typically done through lightweight protocols like HTTP or messaging queues

• Microservices promote flex...read more

React is a JavaScript library for building user interfaces.

• React allows developers to create reusable UI components.

• It uses a virtual DOM for efficient rendering.

• React is often used in conjunction with other libraries like Redux for state management.

• React was developed by Facebook and is maintained by a community of developers.

Variables can hold different types of data, including numbers, strings, booleans, and more, each serving unique purposes.

• 1. String: Represents text, e.g., 'Hello, World!'

• 2. Number: Represents numeric values, e.g., 42 or 3.14.

• 3. Boolean: Represents true/false values, e.g., true or false.

• 4. Array: A collection of values, e.g., [1, 2, 3] or ['apple', 'banana'].

• 5. Object: A collection of key-value pairs, e.g., {name: 'John', age: 30}.

Traits are reusable code blocks that can be mixed into classes, while interfaces define a contract that a class must follow.

• Traits can be used to add methods to a class without inheritance

• Interfaces define a set of methods that a class must implement

• A class can implement multiple interfaces, but can only inherit from one class

• Traits promote code reusability and reduce code duplication

An interface defines a contract for classes, specifying methods and properties without implementation details.

• An interface can be implemented by multiple classes, promoting code reusability.

• Example: In Java, 'Runnable' is an interface that classes can implement to run in a thread.

• Interfaces can contain method signatures and properties but no implementation.

• They enable polymorphism, allowing different classes to be treated as the same type.

• Example: In C#, 'IDisposable' interfa...read more

A filter code is used to sort and display specific data based on certain criteria.

• Filter codes can be used in programming languages like JavaScript to manipulate arrays or objects.

• Examples include using filter() method in JavaScript to filter out elements from an array based on a condition.

• Filter codes can also be used in SQL queries to retrieve specific data from a database.