What is WordPress? A Comprehensive Guide to the World’s Most Popular CMS

Table of Contents#

1. What is WordPress?

   • 1.1 Definition: More Than Just a Blogging Tool
   • 1.2 Open-Source: The Heart of WordPress

2. A Brief History of WordPress

   • 2.1 From b2/cafelog to WordPress: The Early Days
   • 2.2 Key Milestones in WordPress Evolution

3. WordPress.org vs. WordPress.com: What’s the Difference?

   • 3.1 WordPress.org: The Self-Hosted Powerhouse
   • 3.2 WordPress.com: The Hosted Platform
   • 3.3 Which One Should You Choose?

4. Core Features of WordPress

   • 4.1 User-Friendly Dashboard
   • 4.2 Themes: Design Your Site Without Coding
   • 4.3 Plugins: Add Functionality with a Click
   • 4.4 Media Management
   • 4.5 SEO-Friendly Architecture
   • 4.6 Mobile Responsiveness
   • 4.7 User Roles and Permissions

5. How WordPress Works: Under the Hood

   • 5.1 The WordPress Architecture
   • 5.2 The Database: Where Your Content Lives
   • 5.3 The Loop: How WordPress Displays Content
   • 5.4 Frontend vs. Backend: What Visitors and Admins See

6. Who Uses WordPress?

   • 6.1 Beginners and Hobbyists
   • 6.2 Small Businesses and Entrepreneurs
   • 6.3 Bloggers and Content Creators
   • 6.4 Enterprises and Big Brands

7. Common Use Cases for WordPress

   • 7.1 Blogs and Personal Sites
   • 7.2 E-Commerce Stores (WooCommerce)
   • 7.3 Business Websites and Landing Pages
   • 7.4 Portfolios and Creative Sites
   • 7.5 Forums and Community Sites
   • 7.6 Membership and Subscription Sites

8. Getting Started with WordPress.org: A Step-by-Step Guide

   • 8.1 Step 1: Choose a Domain Name
   • 8.2 Step 2: Select a Web Host
   • 8.3 Step 3: Install WordPress
   • 8.4 Step 4: Log In to Your Dashboard
   • 8.5 Step 5: Choose a Theme
   • 8.6 Step 6: Install Essential Plugins
   • 8.7 Step 7: Create Your First Content

9. Advanced WordPress Customization

   • 9.1 Child Themes: Safe Customization
   • 9.2 Custom Post Types (CPTs)
   • 9.3 Page Builders: Drag-and-Drop Design
   • 9.4 Hooks and Filters: Modifying WordPress Core

10. WordPress Security: Protecting Your Site

    • 10.1 Keep WordPress Updated
    • 10.2 Use Strong Passwords and Two-Factor Authentication (2FA)
    • 10.3 Install Security Plugins
    • 10.4 Regular Backups
    • 10.5 Avoid Nulled Themes and Plugins

11. WordPress Performance: Making Your Site Fast

    • 11.1 Why Speed Matters
    • 11.2 Caching Plugins
    • 11.3 Image Optimization
    • 11.4 Choose a Fast Web Host
    • 11.5 Use a CDN (Content Delivery Network)

12. The WordPress Ecosystem: Community and Resources

    • 12.1 The WordPress Community
    • 12.2 Learning Resources
    • 12.3 WordCamps and Meetups

13. Conclusion: Why WordPress Reigns Supreme

14. References

1. What is WordPress?#

1.1 Definition: More Than Just a Blogging Tool#

At its core, WordPress is a free, open-source content management system (CMS). A CMS is software that helps you create, manage, and publish digital content—like text, images, and videos—without needing to write code from scratch.

Originally launched as a blogging platform in 2003, WordPress has evolved into a versatile tool capable of building almost any type of website: blogs, e-commerce stores, portfolios, business sites, forums, and even social networks. Its flexibility is one of its greatest strengths—whether you’re a beginner with no technical skills or an experienced developer, WordPress adapts to your needs.

1.2 Open-Source: The Heart of WordPress#

WordPress is open-source, meaning its source code is freely available for anyone to view, modify, and distribute. This is governed by the GNU General Public License (GPL), which ensures that WordPress remains free to use, even for commercial purposes.

The open-source model fuels WordPress’s growth: thousands of developers worldwide contribute to its codebase, fixing bugs, adding features, and improving security. This collaborative approach has made WordPress not just a CMS, but a global community-driven project.

2. A Brief History of WordPress#

2.1 From b2/cafelog to WordPress: The Early Days#

WordPress traces its roots to 2001, when French developer Michel Valdrighi created a blogging tool called b2/cafelog. In 2003, after Valdrighi stopped developing b2, American developers Matt Mullenweg and Mike Little decided to fork (or rework) the project, naming their new platform “WordPress.”

The first version, WordPress 0.7, launched in May 2003. It introduced basic blogging features like comments, categories, and a simple admin interface. From the start, Mullenweg and Little prioritized user-friendliness and community collaboration—a philosophy that still guides WordPress today.

2.2 Key Milestones in WordPress Evolution#

• 2004: WordPress 1.2 introduces plugins, allowing users to extend functionality without editing core code.
• 2005: WordPress 1.5 adds themes, enabling users to customize their site’s design. The official WordPress Theme Directory launches.
• 2008: WordPress 2.7 overhauls the admin dashboard, making it more intuitive.
• 2010: WordPress 3.0 merges WordPress with WordPress MU (Multi-User), allowing users to manage multiple sites from one dashboard (now called WordPress Multisite).
• 2015: WordPress 4.4 introduces “Responsive Images,” ensuring sites look good on mobile devices by default.
• 2018: WordPress 5.0 replaces the Classic Editor with Gutenberg, a block-based editor that simplifies content creation (you can still use the Classic Editor via a plugin).
• 2023: WordPress 6.4 focuses on performance and design tools, with improvements to the Site Editor (part of the Gutenberg project).

Today, WordPress releases major updates 2–3 times per year, with minor security patches monthly.

3. WordPress.org vs. WordPress.com: What’s the Difference?#

One of the most common misconceptions about WordPress is confusing WordPress.org and WordPress.com. While they share a name, they’re two distinct platforms. Let’s break them down:

3.1 WordPress.org: The Self-Hosted Powerhouse#

• What it is: A free software download (the CMS itself) available at WordPress.org. To use it, you’ll need to host it on a web server (hence “self-hosted”).
• Cost: Free to download and use, but you pay for hosting, a domain name, and possibly premium themes/plugins.
• Control: Full control over your site. You can customize code, install any theme/plugin, and monetize however you want (ads, affiliate marketing, etc.).
• Maintenance: You’re responsible for updates, backups, and security (though tools simplify this).
• Best for: Users who want flexibility, customization, and ownership of their site (e.g., bloggers, businesses, e-commerce stores).

3.2 WordPress.com: The Hosted Platform#

• What it is: A hosted service run by Automattic (the company co-founded by Matt Mullenweg). You sign up, and Automattic hosts your site for you.
• Cost: Free plan available (with WordPress.com branding), but premium plans start at $4/month (Personal) for a custom domain and no ads. Business ($25/month) and Commerce ($45/month) plans unlock more features.
• Control: Limited customization. You can’t install arbitrary plugins/themes on free plans, and monetization options are restricted unless you upgrade.
• Maintenance: Automattic handles updates, backups, and security—great for beginners who want a “set-it-and-forget-it” solution.
• Best for: Casual bloggers, hobbyists, or those who want a simple site without managing hosting.

3.3 Which One Should You Choose?#

• Choose WordPress.org if: You want full control, plan to monetize, or need advanced features (e.g., e-commerce, custom code).
• Choose WordPress.com if: You want a free, low-maintenance site for personal use (e.g., a travel blog with minimal customization).

For most users—especially businesses and serious bloggers—WordPress.org is the better choice due to its flexibility. The rest of this guide will focus on WordPress.org, as it’s the more powerful and widely used option.

4. Core Features of WordPress#

WordPress’s popularity stems from its robust set of built-in features. Even without plugins or themes, it offers everything you need to launch a basic website.

4.1 User-Friendly Dashboard#

The WordPress admin dashboard is designed for simplicity. After logging in, you’ll see a clean interface with menus for Posts, Pages, Media, Appearance, Plugins, and Settings. Beginners can navigate it intuitively, while advanced users can access more technical tools (e.g., Customizer, Site Editor).

4.2 Themes: Design Your Site Without Coding#

Themes control your site’s visual appearance—colors, fonts, layouts, and more. WordPress comes with a default theme (e.g., Twenty Twenty-Three), but thousands of free and premium themes are available in the WordPress Theme Directory and marketplaces like ThemeForest.

Themes range from minimalist blogs to complex e-commerce designs. Many are “drag-and-drop,” allowing you to customize layouts without touching code.

4.3 Plugins: Add Functionality with a Click#

Plugins are like apps for your WordPress site—they extend its functionality. Need a contact form? Install Contact Form 7. Want to sell products? Add WooCommerce. There are over 60,000 free plugins in the WordPress Plugin Directory, plus thousands of premium options.

Popular plugins include:

• Yoast SEO: Optimize your site for search engines.
• WooCommerce: Turn your site into an e-commerce store.
• Akismet: Block spam comments.
• Wordfence: Protect against security threats.

4.4 Media Management#

WordPress makes it easy to upload, organize, and display images, videos, and documents. The Media Library lets you edit images (crop, resize), add captions, and insert media into posts/pages with a click. You can even create galleries and slideshows.

4.5 SEO-Friendly Architecture#

WordPress is built with search engine optimization (SEO) in mind. It generates clean, semantic HTML, and features like permalinks (custom URL structures, e.g., yoursite.com/blog/post-title) help search engines understand your content. Plugins like Yoast SEO or Rank Math take this further, adding tools for meta descriptions, keyword optimization, and XML sitemaps.

4.6 Mobile Responsiveness#

In 2024, over 60% of web traffic comes from mobile devices (source: Statista). WordPress ensures your site looks good on phones and tablets by default—most modern themes are responsive, and the Gutenberg editor lets you preview content on mobile while editing.

4.7 User Roles and Permissions#

If you’re running a multi-author site (e.g., a blog with contributors), WordPress lets you assign roles to users, each with specific permissions:

• Administrator: Full access to all settings.
• Editor: Manages posts/pages, including others’ content.
• Author: Creates and edits their own posts.
• Contributor: Writes posts but can’t publish them.
• Subscriber: Only reads content (useful for membership sites).

5. How WordPress Works: Under the Hood#

To use WordPress effectively, you don’t need to know how it works technically—but understanding the basics helps troubleshoot issues and customize your site. Here’s a simplified breakdown:

5.1 The WordPress Architecture#

WordPress is built with PHP (a server-side programming language) and uses a MySQL database to store content. When a visitor loads your site, the following happens:

1. Their browser sends a request to your web server.
2. The server runs WordPress’s PHP code, which queries the database for the requested content (e.g., a blog post).
3. The PHP code generates HTML, which is sent back to the visitor’s browser, displaying the page.

5.2 The Database: Where Your Content Lives#

Your WordPress database stores everything: posts, pages, comments, user data, theme settings, and plugin configurations. It’s organized into tables (e.g., wp_posts for posts, wp_users for users). You can access the database via tools like phpMyAdmin (provided by most hosts), but you rarely need to edit it directly—WordPress handles this via the dashboard.

5.3 The Loop: How WordPress Displays Content#

The Loop is a PHP code snippet that fetches content from the database and displays it on your site. It’s the backbone of WordPress themes. Here’s a simplified example:

<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
  <h2><?php the_title(); ?></h2> <!-- Displays the post title -->
  <p><?php the_content(); ?></p> <!-- Displays the post content -->
<?php endwhile; endif; ?>

The Loop runs on every page, whether it’s a blog post, homepage, or category archive. Themes use different Loop variations to display content in unique layouts.

5.4 Frontend vs. Backend: What Visitors and Admins See#

• Frontend: The public-facing part of your site (what visitors see when they go to yoursite.com). It’s controlled by your theme.
• Backend: The admin dashboard (accessed via yoursite.com/wp-admin). Here, you create content, install plugins, and customize settings. Only users with login credentials can access the backend.

6. Who Uses WordPress?#

WordPress is used by a diverse range of people and organizations, thanks to its flexibility. Here are the most common users:

6.1 Beginners and Hobbyists#

WordPress’s user-friendly dashboard makes it ideal for beginners. You don’t need to know code to create a blog, portfolio, or personal site. Tools like the Gutenberg editor and one-click plugin installs simplify the process.

6.2 Small Businesses and Entrepreneurs#

Small businesses love WordPress for its low cost (compared to custom-built sites) and scalability. You can start with a basic business site and add features like e-commerce (via WooCommerce) or appointment booking (via plugins) as you grow.

6.3 Bloggers and Content Creators#

WordPress began as a blogging platform, and it’s still the best choice for bloggers. Features like categories, tags, comment moderation, and RSS feeds make it easy to publish and manage content. Plugins like MonsterInsights help track traffic, while affiliate marketing plugins simplify monetization.

6.4 Enterprises and Big Brands#

Even large organizations use WordPress. Examples include:

• BBC America: News and entertainment site.
• Sony Music: Artist profiles and music promotion.
• Time.com: News and magazine content.
• Disney: Some of their sub-brands use WordPress for marketing sites.

Enterprises often hire developers to customize WordPress, but the core platform provides a stable, secure foundation.

7. Common Use Cases for WordPress#

WordPress’s versatility means it can power almost any type of website. Here are the most popular use cases:

7.1 Blogs and Personal Sites#

The classic use case! Whether you’re sharing travel stories, food recipes, or tech reviews, WordPress makes it easy to publish and grow your blog. Features like categories, tags, and social sharing buttons help readers engage with your content.

7.2 E-Commerce Stores (WooCommerce)#

WooCommerce is a free, open-source e-commerce plugin for WordPress that turns your site into a full-featured store. With WooCommerce, you can sell physical/digital products, manage inventory, process payments (via Stripe, PayPal, etc.), and track orders. It powers over 28% of all online stores (source: BuiltWith), making it the world’s most popular e-commerce platform.

7.3 Business Websites and Landing Pages#

Small businesses use WordPress to create professional sites with contact forms, service pages, and about sections. Tools like Elementor or Beaver Builder (page builder plugins) let you design custom landing pages without code, perfect for lead generation.

7.4 Portfolios and Creative Sites#

Artists, photographers, designers, and writers use WordPress to showcase their work. Themes like Divi or Astra offer portfolio-specific layouts, and plugins like NextGEN Gallery help display images. You can even password-protect sections for clients.

7.5 Forums and Community Sites#

Plugins like bbPress (lightweight forums) or BuddyPress (social network features) let you build community-driven sites. For example, a fitness blog could add a forum where users share workout tips, or a brand could create a customer support community.

7.6 Membership and Subscription Sites#

With plugins like MemberPress or Restrict Content Pro, you can create membership sites where users pay for access to premium content (e.g., online courses, exclusive articles). WordPress handles user registration, payments, and content restriction seamlessly.

8. Getting Started with WordPress.org: A Step-by-Step Guide#

Ready to launch your own WordPress site? Here’s how to get started with WordPress.org (self-hosted):

8.1 Step 1: Choose a Domain Name#

Your domain name is your site’s address (e.g., myblog.com). Choose something short, memorable, and relevant to your site’s purpose.

• Where to buy: Namecheap, GoDaddy, or Google Domains (prices start at ~$10/year).
• Tips: Avoid hyphens/numbers, and consider using a .com extension (most users expect it).

8.2 Step 2: Select a Web Host#

Your web host stores your site’s files and serves them to visitors. Look for a host with:

• Speed: Fast loading times (check reviews for “server response time”).
• Reliability: Uptime guarantee (aim for 99.9%+).
• Support: 24/7 customer support (via chat/phone).
• WordPress-specific features: One-click WordPress install, staging sites, and security tools.

Recommended hosts for beginners: Bluehost, SiteGround, or A2 Hosting (prices start at ~$3–$10/month).

8.3 Step 3: Install WordPress#

Most hosts offer one-click WordPress installation:

1. Log in to your host’s control panel (cPanel for most hosts).
2. Look for the “WordPress” icon (often in the “Softaculous” or “Apps” section).
3. Follow the prompts to choose your domain, set an admin username/password, and install.

The process takes 2–5 minutes. Once installed, you’ll receive a link to your site and dashboard.

8.4 Step 4: Log In to Your Dashboard#

Visit yoursite.com/wp-admin and enter the username/password you created during installation. You’ll land on the WordPress dashboard, where you’ll manage your site.

8.5 Step 5: Choose a Theme#

Themes control your site’s design. To install a theme:

1. Go to Appearance > Themes in the dashboard.
2. Click “Add New” and browse free themes (filter by “Featured,” “Popular,” or “Latest”).
3. Hover over a theme and click “Install,” then “Activate.”

Popular free themes: Astra, OceanWP, and Twenty Twenty-Three (default). For premium themes, check ThemeForest or Elegant Themes (Divi).

8.6 Step 6: Install Essential Plugins#

Plugins add functionality. Here are must-have plugins for new sites:

• Yoast SEO: Optimize your site for search engines.
• Akismet: Block spam comments (free for personal sites).
• UpdraftPlus: Backup your site (free version available).
• WP Rocket: Caching plugin to speed up your site (premium, ~$50/year; free alternatives: W3 Total Cache).
• Contact Form 7: Add a contact form to your site.

To install a plugin:

1. Go to Plugins > Add New.
2. Search for the plugin by name.
3. Click “Install Now,” then “Activate.”

8.7 Step 7: Create Your First Content#

Now it’s time to add content! WordPress has two main content types:

• Posts: Time-sensitive content (e.g., blog articles) displayed in reverse chronological order.
• Pages: Static content (e.g., About, Contact, Services) that doesn’t change often.

To create a post:

1. Go to Posts > Add New.
2. Use the Gutenberg editor to add text, images, and blocks (e.g., headings, quotes, galleries).
3. Add a title, category, and tags.
4. Click “Publish.”

Your post will now appear on your site’s blog page!

9. Advanced WordPress Customization#

Once you’re comfortable with the basics, you can customize WordPress further. Here are advanced techniques:

9.1 Child Themes: Safe Customization#

When you customize a theme (e.g., changing CSS), updates to the parent theme will overwrite your changes. A child theme solves this: it inherits the parent theme’s design but lets you add custom code safely.

To create a child theme:

1. Create a new folder in wp-content/themes/ (e.g., twentytwentythree-child).
2. Add a style.css file with a header that references the parent theme.
3. Activate the child theme in the dashboard.

Most premium themes include child themes, or you can use plugins like Child Theme Configurator.

9.2 Custom Post Types (CPTs)#

By default, WordPress has “Posts” and “Pages.” Custom Post Types let you create new content types, like “Products,” “Events,” or “Testimonials.” For example, a restaurant site might use a “Menu Items” CPT.

You can create CPTs manually with code or use plugins like Custom Post Type UI (free) or Toolset (premium).

9.3 Page Builders: Drag-and-Drop Design#

Page builders like Elementor or Beaver Builder let you design custom layouts with a drag-and-drop interface. You can add columns, widgets (e.g., buttons, sliders), and animations without code. Most page builders work with any theme and include pre-made templates.

9.4 Hooks and Filters: Modifying WordPress Core#

Developers can use hooks and filters to modify WordPress’s default behavior without editing core files (which is risky, as updates overwrite changes).

• Actions: Run code at specific points (e.g., after a post is published).
• Filters: Modify data before it’s displayed (e.g., change the site title).

Example of a simple action hook to add text after a post:

function add_custom_text_after_post() {
  echo '<p>Thanks for reading! Subscribe to our newsletter.</p>';
}
add_action( 'the_content', 'add_custom_text_after_post' );

You can add hooks/filters to your child theme’s functions.php file or use a plugin like Code Snippets.

10. WordPress Security: Protecting Your Site#

Security is critical—hacked sites can lose data, damage reputations, or be used for malicious activity. Here’s how to protect your WordPress site:

10.1 Keep WordPress Updated#

WordPress, themes, and plugins release updates to fix security vulnerabilities. Enable automatic updates for minor releases (in Settings > Updates), and update major releases/themes/plugins manually as soon as they’re available.

10.2 Use Strong Passwords and Two-Factor Authentication (2FA)#

• Passwords: Use long, unique passwords (12+ characters with letters, numbers, and symbols). Tools like LastPass generate and store passwords securely.
• 2FA: Add an extra layer of security by requiring a code (sent to your phone or via an app like Google Authenticator) to log in. Plugins like Wordfence or Two Factor enable 2FA.

10.3 Install Security Plugins#

Security plugins scan for threats and block attacks. Top options:

• Wordfence: Free plugin with malware scanning, firewall, and login protection.
• Sucuri: Premium plugin with advanced firewall and DDoS protection (~$199/year).
• iThemes Security: Free version with features like brute-force protection and file integrity checks.

10.4 Regular Backups#

Backups let you restore your site if it’s hacked or crashes. Use a plugin like UpdraftPlus (free) to schedule automatic backups to cloud storage (Google Drive, Dropbox, etc.). Test backups periodically to ensure they work!

10.5 Avoid Nulled Themes and Plugins#

“Nulled” themes/plugins are pirated versions of premium tools. They often contain malware that can hack your site. Always buy from reputable sources (ThemeForest, official developer sites).

11. WordPress Performance: Making Your Site Fast#

A slow site frustrates visitors and hurts SEO (Google prioritizes fast sites). Here’s how to speed up your WordPress site:

11.1 Why Speed Matters#

• User experience: 53% of mobile users abandon sites that take >3 seconds to load (source: Google).
• SEO: Google uses page speed as a ranking factor.
• Conversion rates: Faster sites have higher conversion rates (e.g., more sales, form submissions).

11.2 Caching Plugins#

Caching stores copies of your site’s pages, so the server doesn’t have to generate them from scratch for every visitor. Popular caching plugins:

• WP Rocket: Premium (~$50/year), easy to set up, and highly effective.
• W3 Total Cache: Free, with advanced features for technical users.
• LiteSpeed Cache: Free, optimized for LiteSpeed servers (offered by some hosts like SiteGround).

11.3 Image Optimization#

Images often slow down sites. Optimize them by:

• Resizing: Use tools like Canva or Photoshop to reduce dimensions (e.g., 1200px width for blog images).
• Compressing: Plugins like Smush (free) or ShortPixel (free tier available) reduce file size without losing quality.
• Using modern formats: Convert images to WebP (smaller than JPEG/PNG) via plugins like WebP Converter.

11.4 Choose a Fast Web Host#

Your host has a huge impact on speed. Avoid cheap shared hosting (overcrowded servers slow sites down). Invest in a quality host with SSD storage and fast server response times (e.g., SiteGround, A2 Hosting).

11.5 Use a CDN (Content Delivery Network)#

A CDN stores copies of your site’s static files (images, CSS, JS) on servers worldwide. When a visitor loads your site, the CDN serves files from the nearest server, reducing load times. Cloudflare offers a free CDN with basic features.

12. The WordPress Ecosystem: Community and Resources#

WordPress isn’t just software—it’s a global community of developers, designers, and users. Here’s how to tap into it:

12.1 The WordPress Community#

• Forums: The WordPress Support Forums are free to use. Ask questions, and volunteers will help troubleshoot issues.
• Stack Exchange: WordPress Stack Exchange is a Q&A site for more technical questions.
• Social Media: Join Facebook groups like “WordPress Beginners” or follow #WordPress on Twitter for tips and news.

12.2 Learning Resources#

• WordPress Codex: The official documentation (codex.wordpress.org) is a comprehensive guide (though some pages are outdated; the new WordPress Developer Handbook is better for developers).
• WPBeginner: A blog with tutorials for beginners (wpbeginner.com).
• YouTube: Channels like “WPBeginner” and “Ozh” offer video tutorials.
• Courses: Platforms like Udemy and Skillshare have WordPress courses for all skill levels.

12.3 WordCamps and Meetups#

• WordCamps: Global conferences focused on WordPress (e.g., WordCamp US, WordCamp London). They feature workshops, talks, and networking. Tickets are affordable (~$40–$100).
• Meetups: Local WordPress groups host monthly meetups for users to connect and learn. Find one near you at Meetup.com.

13. Conclusion: Why WordPress Reigns Supreme#

WordPress has dominated the CMS market for over two decades, and for good reason: it’s free, flexible, and backed by a massive community. Whether you’re a beginner building your first blog or a developer creating a custom enterprise site, WordPress adapts to your needs.

Its open-source nature ensures constant innovation, while its ecosystem of themes, plugins, and resources makes it accessible to everyone. With WordPress, the only limit is your imagination.

Ready to start? Head to WordPress.org, download the software, and launch your site today. The internet is waiting.

14. References#

• WordPress.org: https://wordpress.org/
• WordPress.com: https://wordpress.com/
• W3Techs WordPress Usage Statistics: https://w3techs.com/technologies/details/cm-wordpress
• WordPress Codex: https://codex.wordpress.org/
• WPBeginner: https://www.wpbeginner.com/
• WordCamp: https://central.wordcamp.org/
• WooCommerce: https://woocommerce.com/