Website Developer Interview Questions & Answers

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Long polling is a web application development pattern used to emulate pushing data from the server to the client. When the long polling is used, the client sends a request to the server, and the connection remains intact until the server is ready to send data to the client. The connection will be closed only after the data is sent back to the client or connection timeout occurs.

I've often felt that the more I learn, the less I feel like I know. Solving one mystery opens up ten others. Having the interviewee tell you their faults can reveal a lot about what they know.

The advantage of HTTP/2 compared to HTTP/1.1 is

☛ HTTP headers data compression
☛ Server push technologies
☛ Over a single TCP connection parallel loading of page elements
☛ Prioritization of request

Yes, in CSS3, there is a <border-radius> property which allows creating an element with rounded corners. We can apply the same style to all the sides and make the corners round.

The <border-radius> property has four individual properties <border-top-left-radius>, <border-top-right-radius>, <border-bottom-left-radius> and <border-bottom-right-radius>.

In CSS, a class selector is an expression which begins with a full stop (“.”) and followed by the name of a class. The class attribute could be a space-separated list of items, and one of those must match with the class name specified in the selector.

Here is an example which selects a div and modified it style.

.sampleclass {font-family: Ariel; font-size: 10; background: green;}

<div class="sampleclass">....</div>

Find out what inspires them. While it doesn't necessarily "take one to know one," a great developer should always have a few impressive favorites.

CSS3 transitions help to create easy and fast animation effect. They not only give us control to change the value of a property but also let it proceed slowly for the given duration.

We can use the following CSS properties.

transition, transition-delay, transition-duration, transition-property, and transition-timing-function.

Canvas is an HTML5 element which can draw graphics on the fly with the help of JavaScript. The <canvas> element can only contain graphics. It supports a no. of methods for drawing paths, boxes, circles, text, and images.

By default, It has no border. However, it allows using CSS to change the border style.

Weed out the old-school table-driven design junkies! Find a developer who uses HTML elements for what they were actually intended. Also, many developers will say they can go table-less, but when actually building sites they still use tables out of habit and/or convenience. Possibly draw up a quick navigation menu or article and have them write the markup for it. To be tricky, you could draw up tabular data - give them bonus points if they point out that a table should be used in that scenario :)

There is a right answer to this question: all of them. A competent developer should be familiar with testing cross-browser compatibility by using all the major web browsers. Obviously they'll have a primary browser they use for surfing, but their answer to this question might be a good way for you to segue to asking how extensively they test cross-browser issues. Also, if it's some kind of css/html position seeing what toolbars they have installed can be a good metric of their skillset.

HTML5 brought this new ability to store web pages within the browser cache. This web storage is not only faster than the cookies but secured too. It is capable of storing a large amount of data without compromising the performance of the website.

Also, note that the cached data is not must for every server request. Instead, it gets utilized only when the page asks for it. And only the web page which gets the data stored can access it.

The <onload> event doesn’t invoke until the page gets finished loading of CSS and images. It could cause a significant delay in rendering of the web page.

As a web developer, we have to ensure the page should load as quick as possible. The event <onDocumentReady> lets us only wait for the DOM to initialize instead of delaying any action required.

Here are a few points elaborating the differences between Canvas and SVG.

☛ Canvas depends on the resolution whereas SVG doesn’t.
☛ Canvas does not allow event handlers whereas SVG does provide the support for event handlers.
☛ Canvas is ideal for graphic-intensive games whereas SVG doesn’t intend for gaming.
☛ It works well for small rendering areas whereas SVG may perform better for large rendering areas like Google map.

Give them some broken code written in the development language they are expected to know for the position. Have them go through it line by line and point out all the mistakes.

Standards compliance in web development is where everything is (hopefully?) going. Don't ask them to recite the w3c's mission statement or anything, but they should at least have a general idea of who they are.

As per ECMA Script standard, JavaScript is dynamic as well as weakly typed language with first-class functions which means a function can accept other functions as arguments.

Also, it does support auto-type conversion. Whenever an operator or a statement doesn’t get a value of the expected type, then the conversion takes place automatically.

Below are the different types of CSS.

☛ Embedded – It adds the CSS styles using the <style> attribute.
☛ Inline – It adds the CSS to the HTML elements.
☛ Linked/External – It adds an external CSS file to the HTML document.

A good web developer should know

☛ HTML
☛ CSS
☛ SQL
☛ PHP/Ruby/Python
☛ JQuery
☛ JavaScript

See how well they work without their precious GUI. Ask some basic questions like how they would recursively copy a directory from one place to another, or how you'd make a file only readable by the owner. Find out what OSs they have experience with.

This is an important question to ask depending on the work environment. If your project is going to require close interaction with other developers it's very handy to have someone who has had that kind of experience. On the other hand, many developers thrive while going solo. Try to find a developer that fits your needs.

JavaScript allows following types of dialog boxes.

☛ Alert – It just has an <Ok> button to proceed.
☛ Confirm – It pops up a window showing up <Ok> and <Cancel> buttons.
☛ Prompt – It gives a dialog asking for user input followed by showing <Ok>/<Cancel> buttons.

First of all, please note that both the terms <@font-face> and <font-family> refers to changing the font of an HTML element. However, there is a slight difference between the two.

☛ The <@font-face> is a CSS rule that facilitates the use of custom fonts on a web page.
☛ The <font-family> is a CSS property which specifies the font for a web element.

Also, to change the font or face of a font, we need to set the <font-family> property. Please see the below example.

@font-face {
font-family: myCustomFont;
src: url(sansation_light.woff);
}

body {
font-family: 'myCustomFont', Fallback, Ariel;
}

For multi-line text input control, you can use the “textarea tag”.

Find a developer that has experience similar in size to the project you're putting together. Developers with high traffic, large scale site expertise may offer skills that smaller-sized developers don't, such as fine tuning apache or optimizing heavily hit SQL queries. On the other hand, developers who typically build smaller sites may have an eye for things that large scale developers don't, such as offering a greater level of visual creativity.

HTTP/2 provides decreased latency to improve page load speed by supporting:

☛ Data compression of HTTP headers
☛ Server push technologies
☛ Loading of page elements in parallel over a single TCP connection
☛ Prioritization of requests
☛ An important operational benefit of HTTP/2 is that it avoids the head-of-line blocking problem in HTTP 1.