Fundamentals

Some essential concepts, technologies, and protocols serve as the backbone of modern internet applications and services. The most fundamental pillar of communication is the HTTP and HTTPS protocols, which are covered in the networks section.

Apart from this, a solid grasp of other core elements is crucial for anyone looking to build, analyze, secure, or interact with websites and web-based systems.

In this section, we will explore key technologies such as:

• JavaScript, which powers dynamic and interactive content on the client side

• APIs, which enable data and functionality exchange between different systems

• WebSockets, which provide real-time, bidirectional communication capabilities

• The structure and behavior of HTML and CSS

• Persistent client storage (cookies, localStorage, sessionStorage)

• Browser concepts, such as the Document Object Model (DOM)

• Core web security concepts (SOP, CORS, CSP)

• Browser rendering and event handling fundamentals