Web Content Delivery and Request/Response Model

The process of delivering web content (HTML, images, videos, CSS, JS) from servers to users.
Ensures fast, reliable, and scalable content access.

The foundational communication model in web and network interactions.
Client sends request; server processes and sends back response.
Client initiates process by sending a request.
Request consists of:
- Method: Defines the action (e.g., GET, POST, PUT, DELETE).
- URL: Resource being requested (e.g., webpage or API endpoint).
- Headers: Additional metadata like authentication, content type, browser info.
- Body (optional): Data sent to the server (e.g., form data, JSON).
Server receives the request and processes based on:
Method used (e.g., fetching data for GET, updating data for POST).
Resource requested (e.g., HTML page, database query).
Authentication and headers provided (e.g., verifying access permissions).
Server sends a response.
- Status Code: Indicates success or failure (e.g., 200 OK, 404 Not Found, 500 Internal Server Error).
- Headers: Similar to the request, response headers include content type, caching info, and cookies.
- Body (optional): Data sent back (e.g., HTML, JSON, image, file).

GET: Requests data from the server (e.g., loading a webpage, retrieving data via an API).
POST: Sends data to the server, often to create or update resources (e.g., form submissions).
PUT: Updates an existing resource with new data.
DELETE: Removes a specified resource from the server.
PATCH: Partially updates an existing resource.

Initial Pricing vs Renewal Costs: Be aware of renewal pricing.
Hidden Fees: Ensure no extra charges for essential features like SSL, backups, or email accounts.
Money-Back Guarantee: Tests their services risk-free.

Verifies text, images, videos, links, forms, and interactive elements work properly across different browsers, devices, and user scenarios.
Ensures consistent user experience and accessibility.

Text: Readability, error-free, and styled properly.
Images and Videos: Correct display across devices, responsive, and doesn't break the layout.
Links: Hyperlinks and internal/external links work and redirect properly.
Forms: Form fields, validation messages, and submit actions.
Interactive Elements: Buttons, sliders, dropdowns, and navigation work.
Metadata: Page titles, descriptions, and alt text are correct for SEO.

Performance Testing:
- Page Load Speed: Content loads quickly, especially images and videos.
- Cache Testing: Cached versions of content load across users and devices.
- Responsiveness: Content dynamically adjusts to screen sizes without breaking.
Accessibility Testing:
- Use tools like WAVE or Axe to check if content is accessible to people with disabilities.
- Ensure proper use of alt text for images, captioning for videos, and ARIA labels for interactive elements.
- Test keyboard navigation and screen reader compatibility.

Google Lighthouse: Performance, accessibility, and SEO audits.
W3C Validator: HTML and CSS code follow web standards.
Screaming Frog: Crawls website to check for broken links and missing metadata.
Cross-browser Testing Tools: BrowserStack, Sauce Labs, or LambdaTest for checking compatibility.

Ensures compatibility, consistency, and performance across platforms.
Different Rendering Engines: Web browsers use different engines to render content.
User Experience: Different users prefer different browsers.
Feature Support: Features may be supported differently across browsers.
Performance Variations: Browsers handle web resources at different speeds.

Manual Testing: Manually interact with the website on each browser and device.
- Pros: Greater control over visual and functional aspects.
- Cons: Time-consuming and less scalable.
Automated Testing: Using tools like Selenium to run scripts.
- Pros: Faster, scalable, and repeatable.
- Cons: Limited to functional testing, visual bugs may go unnoticed.