Introduction to Front end Developer Interview Questions and Answers
Do you know there are around 1, 673, 535, 333 websites (leaving mobile application) in the world (as of October 2018)? Do you know, there has been a gigantic increase of 800% in the number of internet users (compared to last decade 2008).
Well, this is just a glimpse of the title we are going to cover. But before, let’s take some understanding of it. We will help our readers with a clue – “it is everywhere, on the internet”.
These stats just trifold the pressure for front-end developers across the globe. With every passing second one or more website come into existence and this is an ever-increasing demand. Yes, we will discuss on front-end developer today in our article.
So, to start with what exactly is a frontend developer? What did they do?
Front end means what appears in front of the users (yes, the websites). So, a front end developer implements the structure, design, behavior, and animations related to every bits and piece that you see whenever you open a website or a mobile application.
Now, if you are looking for a job which is related to Front end Developer then you need to prepare for the 2019 Front end Developer Interview Questions. It is true that every interview is different as per the different job profiles. Here, we have prepared the important Front end Developer Interview Questions and Answers which will help you get success in your interview.
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In this 2019 Front end Developer Interview Questions article, we shall present 10 most important and frequently asked Front end Developer Interview questions. These questions are divided into two parts are as follows:
Part 1 – Front end DeveloperInterview Questions (Basic)
This first part covers basic Front end Developer Interview Questions and Answers
Q1. What skill set makes a complete front-end developer? Or what are the crucial skills needed for a front-end developer?
The crucial skill need for a front-end developer are as follow
- Apart from these, there are some more additional skills that can enhance the profile –
- Understanding of cross-browser testing
- Content management systems like WordPress, Joomla, and Drupal
- Knowledge of SEO
Q2. Explain the layers present in a webpage. How CSS plays its role in it?
There are 3 kinds of layers in any web page. These are
- Content Layer
- Presentation Layer
- Behavior Layer
The content layer is the information that a website holds. It comprises of the text details, facts, and the information part.
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Q3. Tell me something about W3C?
W3C stands for World Wide Web Consortium which is an international standard for the web. These people are responsible for standardizing the web and to make it accessible to all users.
Presentation layer will define how the content will appear in front of its users. One can also say it is the look and feel of the web page. Here is the role of CSS a.k.a cascading style sheet is a way to control and present the presentation layer in a web document.
The behavioral layer involves real-time user interaction with the web page.
Q4. Mention some advantages of CSS?
This is the common Front end Developer interview Questions asked in an interview. The advantages of CSS are as follow:
- It saves time
- Helps in fast page loading
- Easy Maintenance
- Superior to HTL style
- Multiple device compatibility
- Global standards for web
- Offline browsing
- Platform Independence
Q5. As a developer what ways are applied to reduce the load time of any given website?
Some crucial things we keep into consideration are –
- Enable a proper browser caching
- Optimize the image files
- Minimize the HTTP requests
- Reduce redirects
Q6. As a developer what ways will you think is crucial to reduce the web application load time?
There are a good number of ways available in doing this, these can reduce the complexity
- Browser caching
- By optimizing the image files
- Resource minify (remove unnecessary characters from source code)
- Minimize HTTP request
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By using this syntax –
Var myArray = [ [  ] ];
Part 2 – Front end Developer Interview Questions (Advanced)
Let us now have a look at the advanced Front end Developer Interview Questions.
Q8. What would be the result of 9+6+”3”?
The o/p will be 153.
Explanation – here 9 and 6 are datatypes (integers) so they will be added numerically. Since 3 is a string the result would be concatenated and become as 9+6 = 15 and 3 come together to form 153 as output.
Q9. Explain the CSS box model?
The Box model helps in providing a more structured way to space elements in relation to each other for a web page. The box model has several components in it like
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Q10. What is CSS pre-processor? Why do we use them?
Pre-processor is used for code conversion. The preprocessed languages like SASS and LESS are converted to more formal CSS format. Reasons for using them are
- Ability to define variables
- Ability to use nested syntax
- Ability to create and use mixins (functions)
- Use of mathematical and operational functions
Q11. Name some of the new features present in HTML5 and are missing in HTML?
This is the frequently asked Front end Developer Interview Questions in an interview. Some new features in HTML5 are –
- DOCTYPE declaration
- Section tag (<section/. …</section>)
- Header and Footer tag
- Flgcaption tag
Q12. Tell me the components of a CSS style?
The CSS style is made up of three things
- Selector: A selector is an HTML tag where styles can be applied. A selector tag can be anything of <h1> or <table>
- Property: This is an attribute of HTML tag. This property can be anything like colors, border, shades etc. The HTML attributes are converted into CSS property.
- Value: A value is always assigned to any defined properties.
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Q13. Can you explain ways to apply CSS styles to a web page?
The first way to do it by using the inline style attributes on an element,
- <p style=”color: maroon; “></p>
One can use a <style> block in the <head> section of the HTML
Lastly, using the <link> tag while loading the external CSS file
The 3 main ways to do this is –
- parseInt ()
- parseFloat ()
This has been a guide to the list of Front end Developer Interview Questions and Answers so that the candidate can crackdown these Front end Developer Interview Questions easily. Here in this post, we have studied top Front end Developer Interview Questions which are often asked in interviews. You may also look at the following articles to learn more –