App & Browser Testing Made Easy

Give your users a seamless experience by testing on 3000+ real devices and browsers. Don't compromise with emulators and simulators

Home Guide What is a Browser and How do they work?

What is a Browser and How do they work?

By Kitakabee, Community Contributor -

Web browsers play an integral role in the way we interact with the internet. They’re the gateway to the vast online universe, allowing us to shop, learn, communicate, entertain ourselves, and much more.

This article will help you understand the basics of web browsers, unraveling the technology that connects us to the countless corners of the internet. 

If you’ve ever been curious about how your request transforms into a full-fledged website on your screen or how a browser protects your data while ensuring an optimized experience, read on. 

What is Browser?

A web browser is a software that enables users to access and view content on the World Wide Web. Its primary function is to locate and retrieve web pages, images, videos, documents, and other files from servers and display them on the user’s device.

For instance, imagine you want to visit a website. Here’s where the browser comes in. When you type the website’s URL into the browser’s address bar and hit Enter, your browser sends a request to the server where the website’s files are stored. This communication happens over protocols such as HTTPS (Hypertext Transfer Protocol Secure) or HTTP (Hypertext Transfer Protocol).

On receiving your request, the server sends back the website’s files. These files are often written in languages like HTML, CSS, and JavaScript. Your browser’s job is to interpret this code and render it into the web page you see.

In essence, the browser acts as a bridge between you and the website, sending your requests to the server and translating the server’s response into a format you can easily interact with on your device. Without a browser, navigating the vast ocean of internet content would be nearly impossible.

Evolution of Browsers 

The first web browser – or browser editor – was called WorldWideWeb. It was invented by Sir Tim Berners-Lee in 1990.

During the initial era of the browsers, names like Mosaic, Netscape Navigator, and Internet Explorer dominated the industry. 

But the industry has evolved in the past three decades because of improvements in performance, security aspects, and better user customization.

Here is the list of modern browsers that rule the industry:

  • Google Chrome
  • Mozilla Firefox
  • Apple Safari
  • Microsoft Edge
  • Opera
  • Brave
  • Vivaldi
  • Tor Browser
  • UC Browser
  • Samsung Internet

These modern browsers offer multiple features that help them deliver the best browsing experience to the users. 

Functions of a Browser

A web browser serves a multitude of functions to enhance your browsing experience. Let’s explore some of the key features and functions of a browser:

  1. Web Page Rendering: When you visit a website, the browser retrieves the website’s HTML, CSS, and JavaScript files from the server. It then interprets and processes this code to construct the web page you see on your device. The HTML defines the structure and content of the page, CSS styles the page’s appearance, and JavaScript adds interactivity and dynamic elements.
  2. Navigation: Browsers provide an intuitive interface for navigating the internet. You can enter a website’s address (URL) directly into the address bar, and the browser will take you to that specific webpage. Additionally, you can click on hyperlinks within web pages to navigate to other related pages. Browsers also support bookmarks, which allow you to save and organize frequently visited websites for quick access.
  3. Tabbed Browsing: Tabs revolutionized web browsing by allowing you to open multiple web pages within a single browser window. Instead of opening separate browser instances for each webpage, you can open new tabs, each representing a different webpage. This feature facilitates multitasking and makes it easy to switch between different websites without cluttering your screen.
  4. Bookmarks and History: Browsers enable you to save your favorite websites as bookmarks. Bookmarks act as shortcuts, allowing you to quickly revisit those websites without having to remember their URLs. Browsers also maintain a history of the websites you’ve visited, providing a chronological record that you can browse through to revisit previously viewed web pages.
  5. Search Functionality: Browsers often include a search bar, typically located in the toolbar. This search bar is integrated with popular search engines like Google, Bing, or DuckDuckGo. Instead of navigating to a search engine’s website, you can directly enter keywords or phrases into the search bar. The browser sends your search query to the chosen search engine, which then displays relevant search results.

Components of a Browser

A browser has two elements: front-end and back-end. The complex back end facilitates the core functioning of the browser, and the front end interacts with the user. Let’s dive a bit deeper: 

  • Front-end: The front-end of a browser refers to the user-facing part that you interact with. It includes the graphical user interface (GUI) elements, such as the address bar, navigation buttons, bookmarks, and tabs. The front-end also handles the rendering of web pages, displaying the content, images, and interactive elements on your device’s screen. 
  • Back-end: The back-end of a browser encompasses the complex processes that occur behind the scenes. It handles the communication between the browser and web servers, fetching and managing web page resources, and processing the code that makes up the web pages. The back-end interprets HTML, CSS, and JavaScript files, ensuring that web pages are rendered correctly. It manages network connections, supports various protocols like HTTP and HTTPS, and handles security measures such as encryption and certificate verification..

The front-end and back-end components of a browser work together seamlessly to provide a rich and interactive browsing experience. 

When you interact with the front-end by typing a URL, clicking on links, or using browser features, the front-end communicates with the back-end to fetch the necessary web page resources. 

The back-end processes these resources and sends the rendered content back to the front-end for display on your device. This collaboration between the front-end and back-end enables you to navigate the internet, access websites, and interact with online content smoothly.

Apart from these two major elements, here are the components of a browser.

Components of a browser

  • User Interface: The user interface is the space where users interact with the browser. It encompasses elements such as bookmarks, an address bar for entering website URLs, back and forward buttons for navigation, tabs for multitasking, and menus for accessing various browser features and settings. The user interface provides a visually intuitive way for users to control and navigate the browser.
  • Browser Engine: The browser engine acts as the core of the browser, handling user interactions, rendering web pages, and facilitating communication with other components. It coordinates the flow of information between the user interface, rendering engine, and other browser components. The browser engine ensures that user actions, such as clicking a link or entering a URL, are properly processed and trigger the appropriate actions within the browser.
  • Rendering Engine: The rendering engine is responsible for displaying the content of web pages within the browser. It takes the HTML, CSS, and JavaScript code of a web page and converts it into a visual display that users can see. The rendering engine interprets the HTML structure, applies the CSS styles to determine the page’s layout and appearance, and executes any JavaScript code to add interactivity and dynamic elements to the web page.
  • JavaScript Interpreter: The JavaScript interpreter is a component within the browser that executes JavaScript code found on web pages. JavaScript is a programming language commonly used for adding interactivity and dynamic functionality to websites. The interpreter ensures that JavaScript code is properly executed, allowing web pages to respond to user actions, update content dynamically, and interact with APIs and other web technologies.
  • Networking: The networking component of a browser handles various aspects of network communication. It is responsible for resolving website URLs into IP addresses, sending HTTP requests to web servers, establishing network connections, and receiving and processing the responses. The networking component plays a crucial role in fetching web page resources, such as HTML, CSS, images, and other files, from servers and delivering them to the rendering engine for display.

Each browser component is important and they work together to give a seamless experience while using a browser.

How does a Browser Work? 

Browsers are responsible for retrieving and displaying web content to users. When a user enters a URL or clicks on a link, the browser initiates a complex series of actions to retrieve the web content from a server and display it on the user’s device.

How does a Browser Work

The process begins with Domain Name System (DNS) resolution, where the browser translates the domain name into an IP address to locate the server where the web page is stored. 

  • The browser then sends an HTTP request to the server, specifying the path and parameters of the requested resource.
  • Once the server receives the request, it sends an HTTP response to the browser containing the requested resource in HTML, CSS, and JavaScript code. 
  • The browser’s rendering engine interprets and renders the code to display the web page on the user’s device. 
  • The CSS stylesheets are applied to format the web page’s content, including fonts, colors, and layout.
  • The browser may also execute JavaScript code on the web page to add interactivity and dynamic behavior. 

As new content is loaded or changes are made to the web page, the browser updates the display accordingly.

Apart from the working principles, there are a few terms related to browsers that you must know.

Commonly used Jargons in Browser

A few commonly used jargon around browsers are:

  • URL: The universal resource locator (URL) addresses a unique resource on the web. 
  • HTML: HyperText Markup Language (HTML) is used for creating web applications and pages. 
  1. HTTP: Hypertext Transfer Protocol (HTTP) allows the fetching of resources, like HTML documents.
  2. HTTPS: Hypertext Transfer Protocol Secure (HTTPS) works as HTTP but with encryption for a secure server communication.
  3. IP Address: It spots the location of a specific server connected to the internet.
  4. DNS: Domain Name System is a database containing domain records.
  5. Cookies: Cookies are small text files that are stored on the user’s device by a website. When a user visits a website, the website may create a cookie to track information about the user’s activity on the site or to remember the user’s preferences or login information.

Based on the browser’s type managing the cookies can vary.

Types of Browsers 

There are several types of browsers available for users, including:

  • Desktop browsers: These are the most common browsers that users install on their desktop computers or laptops. Examples include Google Chrome, Mozilla Firefox, Microsoft Edge, Apple Safari, and Opera.
  • Mobile browsers: Browsers designed specifically for mobile devices such as smartphones and tablets are called mobile browsers. Examples include Google Chrome for Android and iOS, Safari for iOS, Firefox for Android, and Opera for Android and iOS.
  • Console browsers: These are designed for game consoles such as Xbox and PlayStation, allowing users to browse the web from their consoles.
  • Text-based browsers: Legacy browsers that only display websites as text, without graphics or images, are text-based. Examples include Lynx and Elinks.

Different browsers have their interpretations of Open Web Standards. 

Since they each render CSS, HTML, and JavaScript uniquely, thoroughly debugging your website’s code is not enough to ensure that your website will look and behave as intended on multiple browsers.

This is where browser compatibility becomes crucial. Browser compatibility refers to the ability of a website or web application to function consistently across different browsers and their various versions. It ensures that users receive a consistent user experience regardless of the browser they use to access the website.

People use different browsers based on their personal preferences, device compatibility, and platform availability. Some popular browsers include Google Chrome, Mozilla Firefox, Microsoft Edge, Safari, and Opera. Each of these browsers has its own rendering engine, which interprets and displays web content in its unique way. This diversity makes it essential for website developers and companies to test their websites and applications on different browsers.

Companies invest in browser compatibility testing to ensure that their websites and applications are accessible, visually appealing, and function properly across multiple browsers. By testing their web assets on different browsers, companies can identify and address any inconsistencies or compatibility issues that may arise. This ensures that their target audience, regardless of their preferred browser, can have a consistent and satisfactory experience.

Additionally, companies need to consider the diverse range of devices and operating systems used by their audience. Websites and applications must be tested across various platforms, including desktop computers, laptops, tablets, and smartphones, to ensure optimal performance and user experience. 

That’s where you can rely on cross-browser testing, which helps pinpoint browser-specific compatibility errors so you can debug them quickly. 

It helps ensure you’re not alienating a significant part of your target audience–simply because your website does not work on their browser OS.


Browsers have been part of the internet ecosystem since the start. The future of browsers will likely revolve around several key areas:

  • Privacy and Security: As privacy concerns grow, browsers are expected to prioritize user privacy by implementing enhanced security measures, stricter data protection, and better control over personal information.
  • Performance and Speed: Browsers will continue to strive for improved performance and faster loading times, enabling users to access web content quickly and efficiently.
  • Integration with Devices and Platforms: With the increasing prevalence of interconnected devices and platforms, browsers will focus on seamless integration and compatibility across different devices, operating systems, and platforms.

To ensure a smooth user experience across multiple web applications, it is crucial to have access to a robust testing platform. 

BrowserStack offers a comprehensive solution by providing a real device cloud with instant, on-demand access to over 3000 browsers and devices. This allows developers and testers to perform extensive testing across a wide range of configurations and ensure compatibility across various browsers and devices.

It offers a real device cloud with instant, on-demand access to over 3000 browsers and devices.

Try BrowserStack Now 

Website Testing

Featured Articles

Understanding Browser Market Share: Which browsers to test on in 2023

What is Browser Automation?

Curated for all your Testing Needs

Actionable Insights, Tips, & Tutorials delivered in your Inbox
By subscribing , you agree to our Privacy Policy.
thank you illustration

Thank you for Subscribing!

Expect a curated list of guides shortly.