Walstar Technologies Interview Questions and Answers

Semantic HTML elements clearly describe their meaning in a human- and machine-readable way, enhancing accessibility and SEO.

• Examples include <header>, <footer>, <article>, and <section>.

• These elements provide structure and meaning to web pages.

• Using semantic elements improves accessibility for screen readers.

• They help search engines understand the content better.

Event delegation is a technique in JavaScript that allows handling events at a higher level in the DOM tree.

• Event delegation utilizes the event bubbling phase to manage events efficiently.

• Instead of attaching event listeners to individual elements, a single listener is added to a parent element.

• This approach reduces memory usage and improves performance, especially with many child elements.

• Example: Instead of adding cl...read more

React Hooks are functions that let you use state and other React features without writing a class.

• Hooks allow functional components to manage state and lifecycle events.

• Common hooks include useState for state management and useEffect for side effects.

• Example of useState: const [count, setCount] = useState(0);

• Example of useEffect: useEffect(() => { document.title = `Count: ${count}`; }, [count]);

• Custom hooks can be c...read more

Closures in JavaScript allow functions to retain access to their lexical scope even when executed outside that scope.

• A closure is created when a function is defined inside another function.

• The inner function has access to the outer function's variables.

• Example: function outer() { let x = 10; return function inner() { return x; }; }

• Closures are often used for data encapsulation and creating private variables.

• They can al...read more

Two-way data binding in Angular allows automatic synchronization between the model and the view.

• Uses the ngModel directive to bind input fields to component properties.

• Changes in the input field update the model, and vice versa.

• Example: <input [(ngModel)]='username'> binds 'username' property to the input.

• Facilitates easier form handling and validation in Angular applications.

HTML5 is the latest version of HTML, introducing new features, elements, and APIs for modern web development.

• HTML5 introduces new semantic elements like <article>, <section>, and <header> for better structure.

• HTML5 supports multimedia elements like <audio> and <video> without needing third-party plugins.

• HTML5 includes new form input types such as <input type='date'> and <input typ...read more

I use Git for version control, enabling collaboration, tracking changes, and managing code efficiently across projects.

• Git: A distributed version control system widely used for tracking changes in source code during software development.

• GitHub: A cloud-based platform that hosts Git repositories, facilitating collaboration and code sharing among developers.

• GitLab: Similar to GitHub, it offers repository hosting along wi...read more

HTML5 is the latest version of HTML, introducing new features, elements, and APIs for modern web development.

• HTML5 introduces new semantic elements like <article>, <section>, and <nav> for better structure.

• HTML5 supports multimedia elements like <audio> and <video> without needing third-party plugins.

• HTML5 includes new form input types such as <date>, <email>, and <range>...read more

A good website combines usability, design, content, and performance to create an engaging user experience.

• User-Friendly Navigation: Clear menus and intuitive layout help users find information easily. Example: Amazon's categorized navigation.

• Responsive Design: Websites should work well on all devices, from desktops to smartphones. Example: Bootstrap framework.

• Fast Loading Speed: Pages should load quickly to reduce boun...read more

PHP 7 offers significant performance improvements and new features compared to PHP 5, enhancing development efficiency.

• Performance: PHP 7 is up to twice as fast as PHP 5 due to the new Zend Engine.

• Type Declarations: PHP 7 introduced scalar type hints (e.g., int, float) for better type safety.

• Error Handling: PHP 7 uses Throwable interface for better error handling with exceptions.

• Null Coalescing Operator: PHP 7 introduc...read more

Namespaces in PHP help organize code and avoid name collisions in larger applications.

• Namespaces allow grouping of related classes, functions, and constants.

• They prevent naming conflicts when using libraries or frameworks.

• Defined using the 'namespace' keyword at the beginning of a file.

• Example: namespace MyApp\Controllers; defines a namespace for controllers.

• Use 'use' keyword to import classes from a namespace, e.g., u...read more

SEO tools help analyze, optimize, and track website performance to improve search engine rankings.

• Google Analytics: Tracks website traffic and user behavior.

• SEMrush: Offers keyword research, site audits, and competitor analysis.

• Ahrefs: Provides backlink analysis and keyword tracking.

• Moz: Features tools for keyword research and site optimization.

• Yoast SEO: A WordPress plugin that helps optimize content for search engine...read more

Google AdWords is an online advertising platform that allows businesses to create ads for Google search results and display networks.

• AdWords operates on a pay-per-click (PPC) model, meaning advertisers pay only when users click their ads.

• Ads can appear on Google search results pages, as well as on partner websites through the Google Display Network.

• Advertisers can target specific keywords, demographics, and locations t...read more