WSAT Lesson 1 - Introduction to Web Systems and Technologies.pdf

The World Wide Web, a vast interconnected network of information, has become an integral part of our daily lives. At its core, the web is a system of interconnected computers, or servers, that store and deliver information. To access and interact with this information, we use web browsers, which act as intermediaries between our devices and the servers. This interconnectedness, facilitated by a set of protocols and standards, is what defines a web system.

Fundamental Components of Web Systems
A typical web system consists of several key components:

Server: A computer that stores and delivers web pages, images, and other digital content. It acts as the host for a website.
Client: A device (e.g., computer, smartphone, tablet) that requests and receives information from a server through a web browser.
Web Browser: Software that interprets HTML code and displays web pages on a client device. Examples include Chrome, Firefox, Safari, and Edge.
Hypertext Markup Language (HTML): The standard markup language used to create web pages. It defines the structure and content of a page, including text, images, links, and other elements.
Cascading Style Sheets (CSS): A language used to style HTML elements, controlling their appearance, layout, and formatting.
JavaScript: A programming language that adds interactivity to web pages, enabling dynamic content, user interactions, and client-side scripting.
Database: A structured collection of data that can be accessed and managed by a database management system (DBMS). Databases are often used to store and retrieve information related to web applications.
Application Server: A software program that handles requests from clients and interacts with databases to retrieve and process data.
How Web Systems Work
When a user types a URL into a web browser, the browser sends a request to the server hosting the corresponding web page. The server processes the request, retrieves the HTML file, and sends it back to the browser. The browser then interprets the HTML code, rendering the content on the screen.

If the web page requires additional resources, such as images or JavaScript files, the browser will send additional requests to the server. The server will respond by sending the requested files, which the browser will then load and display.

Types of Web Systems
Web systems can be categorized based on their complexity and functionality:

Static Websites: These websites have fixed content that doesn't change dynamically. They are typically built using HTML and CSS.
Dynamic Websites: These websites can generate content on the fly, often using server-side scripting languages like PHP, Python, or Ruby. They can interact with databases and provide personalized experiences.
Single-Page Applications (SPAs): SPAs load the entire application into the browser as a single page and then update the content dynamically using JavaScript. This can provide a more responsive and fluid user experience.
Content Management Systems (CMS): CMS

1. Lesson 1 – Web Systems and Technologies
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