In-depth Notes on Internet, Web Technologies, and Class Structure

  • Internet: A global network of interconnected computers that communicate through standardized protocols. It enables myriad applications and services, ranging from browsing web pages to streaming media.

  • The Web: A vast information system that allows users to access and share content using web browsers, and is built on technologies such as HTML, CSS, and JavaScript.

Introduction to the Internet vs. the Web

  • Definition of Internet: A global network of computers sharing information.

  • Definition of Web: Uses internet resources to transmit data via HTTP and HTML.

  • Key Distinction: The Internet provides access; the Web is a collection of data transmitted over that network.

Analogies for Understanding:

  • Campus Roads: Internet as roads connecting dorms; web as the content accessible from those dorms.

  • Traffic Types: Various internet traffics such as emails and media, similar to multiple vehicles on roadways.

Clients and Servers

  • Definition: The web operates on a client-server model.

    • Clients: Devices (browsers, mobile apps) requesting information.

    • Servers: Devices (data centers) that store and respond to requests.

Data Centers

  • Role: Data centers are vital for internet functionality.

  • Location Note: Virginia has the largest concentration of data centers.

  • Energy Impact: Data centers are straining energy resources.

Technical Details

Clients:

  • Devices such as phones and computers initiating requests.

  • Technologies:

    • HTML & HTML5

    • JavaScript & jQuery

Servers:

  • Store content and fulfill information requests.

  • Technologies:

    • PHP

    • ASP.NET

Request Workflow

  1. User interaction (clicking a hyperlink or entering URL).

  2. Request sent to a server via internet.

  3. DNS translates URL to IP address.

  4. Browser contacts web server using IP.

  5. Server processes request and sends back data.

Communication Protocols

  • HTTP (Hypertext Transfer Protocol): Core for data transfer between clients and servers.

  • FTP (File Transfer Protocol): For uploading/downloading files.

  • TCP/IP: Fundamental protocols for data communication.

  • SMTP (Simple Mail Transfer Protocol): For sending emails.

Understanding Domain Names

  • Components of a URL (example: http://www.jmu.edu):

    • Top-level domain: .edu

    • Domain name: jmu

    • Host name: www

    • Protocol: http

URLs Explained

  • Example URL: http://www.google.com/search?q=facebook#result

    • Breakdown:

      • Protocol: http

      • Domain: www.google.com

      • Path: /search

      • Parameters: ?q=facebook

      • Fragment: #result

Web Standards & Best Practices

  • W3C (World Wide Web Consortium): Establishes standards for web technologies (HTML, CSS).

  • Validator Tool: Checks code for adherence to standards to ensure cross-platform compatibility.

Front-end vs. Back-end Development

Front-end Design:

  • Concerned with the client-side visible to users.

  • Technologies: HTML, CSS, JavaScript.

Back-end Development:

  • Encompasses server-side operations and database interactions.

  • Technologies: PHP, MySQL, ASP.NET.

HTML and CSS

  • HTML: Structures web pages (version HTML5).

  • CSS: Styles web aesthetics (version CSS3), includes pre-processors like SASS.

To Prepare for Wednesday

  • Guest Speaker: Prepare questions for Patrick from www.campquiet.com.

  • LinkedIn Learning: Complete assigned course by next week.