Key technologies for the front-end developer

29.04.2022 Angelika Siczek

What is the front-end of a website? It is everything you can see in your browser when you type in the address of a website. A front-end developer is just involved in creating its visual part. Appropriate tools are needed to do that. The most frequently used are HTML, CSS or JavaScript. Below we present a detailed description of key technologies, which are needed for front-end web development.

Creating Websites Using HTML

For the purpose of creating any software as well as a website, a special  language is needed. HTML is the most often used language for the front-end development. With its support, you can easily define the basic structures of a webpage, such as headings, paragraphs or the arrangement of individual elements in relation to each other.

Basic Elements of HTML

When writing in the HTML markup language, tags are used. These are short terms in the triangular brackets. They are responsible for delineating the individual elements of the webpage. Two key tags are <html>, which starts the description of the webpage, and <body>, which defines a content visible to the user. At the end of the document, you can find </body> and </html>. They mark the end of the descriptions of the aforementioned elements. Other tags enable you to create headings, paragraphs, embed images, charts, videos and other media.

The HTML language is constantly evolving. Since 1991, when it was first released, it has undergone many significant changes and updates. The current latest version is HTML5, in use since 2014. It has functions such as off-line media storage and more elements that allow you to create a webpage.

Formatting a Style with the Use of CSS

Cascading Style Sheets (abbreviation CSS) is a language that enables the creation of formatting styles. It is responsible for the appearance, layout and responsiveness of a webpage. CSS descriptions interact with HTML. This is done with the help of selectors. They define which HTML elements will be modified by a given CSS function. The most important style elements are:

  • font size,
  • font colour,
  • margins,


and many other elements for formatting text or headings.

How is a CSS Code Implemented in HTML?

There are three manners of such an implementation. The choice of a right method depends on a particular situation and needs. The CSS code may be included in the external style sheets as the separate files. In this solution once defined style can be used multiple times within the different HTML documents, which makes it much easier to work with very large projects. The CSS instructions can also be placed in the heading of a given webpage in a HTML file. Then they are valid for this single webpage and can be used multiple times. Finally, the CSS instruction can be written directly in the HTML code, if it is a local formatting, used only in a single case.

By using all three measures, you can keep your code in the right order, which will make it much easier to make changes in the future. By keeping your code clear, you can also avoid serious problems when changing individual style parameters.

CSS Frameworks

Frameworks are ready-made sets of the CSS and HTML files. They allow to significantly speed up the work of the software developer, because you do not have to write standard styles and elements of the page, but only edit these parameters, which are relevant in a given case. There are fully functional and extensive frameworks such as Bootstrap, Semantic UI, a bit less developed, used for a material design – Materialize CSS and Material Design Lite, and also completely designated as Pure.


Writing CSS instructions can be automated to a large extent thanks to pre-processors. These take care of, inter alia, checking colour values and closing tags, among other things. They also make it easier to repeat certain operations in the different places in the CSS document. At the end of the job, the pre-processor compiles to a plain CSS code and can be used in a standard way. The most well-known examples of such programmes are Sass and LESS.

Structure of a Webpage

DOM is an object-oriented application programming interface that serves as a software interface for the HTML and XML documents. Thanks to it, programmes are capable to interpret individual elements of a webpage and modify their style. This document structure allows the document to be easily modified using scripting languages, of which JavaScript is the most widely recognised.

More Interactivity

Scripting languages allow you to bring much more life and user interaction to your website. In this manner, both the front-end and the back-end is supported. In this case, however, we are interested in using this tool in the former area. Thanks to JavaScript, you can create animated interface elements such as sliders or pop-ups. Furthermore, it enables the user to make choices and enter them on the webpage without having to reload the entire website.

As in the case of CSS and HTML, scripting languages also offer templates with the most frequently used functions. In this event, they are called frameworks. There are also pre-written code snippets that significantly speed up a development of front-end. Examples of frameworks are Angular, Vue.Js or Ember.Js. However, libraries that support code development are React, JQuery and D3.Js. These are the most identifiable examples.

Combining Front-end and Back-end

We have focused in this article on back-end development, but it cannot exist without front-end development. Therefore, tools to communicate between these areas are also needed. A few years ago, an asynchronous approach prevailed. It allows to refresh only the part of the webpage that requires changes (for example, adding a new filter on the product list does not cause reloading of the whole webpage, but only the product list itself). XML used to be helpful in this respect, although later mainly JSON was used. Currently, REST and GraphQL are employed.

News Digitized / Stay Informed

Since the beginning of 2022, we are part of Unity Group. Now, by signing up for our newsletter, you will be kept up to date with information from our entire organization.

    By submitting the form you agree to receiving a newsletter that is sent by Unity S.A. based in Wrocław. You can withdraw your consent at any time. Additional information about the processing of available details provided in the privacy policy.



    Andrzej Szylar

    Chief Executive Officer


    Magdalena Paczyńska-Kamienik

    HR Manager


    Aleksandra Bielawska-Clegg

    HR Business Partner



    Michał Duława

    New Business Developer



    Katarzyna Zajchowska

    Marketing Partner