UI developer interview questions and answers

Web UI developer also known as Front end developers who build web pages using the primary technologies of a website such as HTML5, CSS3, JavaScript and Jquery based on the given PSD or JPEG visual design of the web page. New generation UI developers are using CSS frameworks like Twitter BootStrap, Sematic UI and Optionally using a Javascript Framework like AngularJs Or ReactJss and some supporting tools like Grunt, Gulp, Eslint these suppoting tool works using NodeJs. If you are familiar with Adobe Photoshop or Illustrator it will be a plus point. If you are going for an interview for the post of a UI developer you must be good in the primary UI development technologies. If are going to attend the interview in the top MNC IT companies like TCS, Cognizant, Infosys, Wipro etc then you must cover all basic CSS styling methods and must be aware about the usage of all HTML4 and HTML5 features, tags and the Usage of both Jquery and Javascript. I have listed few important interview questions for beginners. Download the questions as a pdf file

HTML Questions

  1. How html5 is different from html4?

    HTML5 is an upgraded version of html4.01 and introduced some new features such as Audio, Video, Canvas, Drag & Drop, Storage, Geo Location, Web Socket etc and also introduced some new html tags such as article, section, header, aside and nav etc which help to create the page layout faster. HTML 5 will handle the inaccurate syntax of the tags and it simplified the doctype and character set declaration. It also deprecated some html tags like center, font, strike, acronym, applet etc.

  2. How browsers detect the html version of a webpage?

    We must declare the doctype at the top of the page, it is an instruction to the web browser about what version of HTML the page is written in.

  3. Write down the Doctype declaration of html5 and html4


    <!DOCTYPE html> 
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">

  4. What are the new form attributes in HTML5 ?

    Placeholder, novalidate, autocomplete, required , autofocus, pattern, list, multiple, formnovalidate etc

  5. What are the different units for expressing a length in css?

    rem, vh, vw, ex, ch, em, %, px, in, cm, mm, pt and pc

    Unit Description
    em 1 em is the computed value of the font-size on the element on which it is used.
    ex 1 ex is the current font’s x-height. The x-height is usually (but not always, e.g., if there is no ‘x’ in the font) equal to the height of a lowercase ‘x’
    ch 1 ch is the advance of the ‘0’ (zero) glyph in the current font. ‘ch’ stands for character.
    rem 1 rem is the computed value of the font-size property for the document’s root element.
    vw 1vw is 1% of the width of the viewport. ‘vw’ stands for ‘viewport width’.
    vh 1vh is 1% of the height of the viewport. ‘vh’ stands for ‘viewport height’.
    vmin Equal to the smaller of ‘vw’ or ‘vh’
    vmax Equal to the larger of ‘vw’ or ‘vh’
  6. What is SVG?

    SVG stands for Scalable Vector Graphics, It is an XML based two-dimensional vector graphics image format.

  7. What is character encoding in HTML ?

    Character encoding is a rule for how to interpret raw zeroes and ones into real characters. There are two main character encoding representations used in html documnets such as UTF-8, and ISO-8859-1. The default character set for HTML5 is UTF-8. The following syntax is used to set the character encoding in an html document <meta charset="UTF-8">

  8. What is HTML Entities ?

    HTML Entities are some special words which is used to replace the reserved characters or some other characters that are not present on your keyboard can also be replaced by entities in your HTML, For example if you need to display < ( 'Less than' symbol ) In your html document, You can use &lt; Entity

  9. What is mean by Responsive Web Site ?

    It will looks good in all screen resolutions device type. We can utilize css media quries to re-arrange the with of an element also we can hide or display any elements in a web page. Bootstrap is a widely using css framework to make responsive web pages quikly

  10. List out some HTML5 tags

    header, footer, main, nav, section, article, aside etc..

  11. What is the use of HTML5 Canvas element ?

    It is used to draw graphics on a web page by the help of javascript.

  12. What is the use of 'placeholder' attribute in HTML5?

    It is used to display some text with in a textbox or textarea and the text will disappear when user start typing in that box