Essential FREE WordPress Plugins to Use in 2020

Did you know that the official plugin repository has over 55,000+ WordPress plugins and counting? That means there are plugins (Paid and Free WordPress Plugins) for almost every function or feature you need on your website. 

WordPress plugins are great tools for adding and extending functionality to WordPress.  In this post, I will discuss essential WordPress plugins you should have on your WordPress website. 

These plugins here are not for every site. Yes, you heard it right. Some of the plugins are specially designed for particular sites like WooCoomerce plugin is for shopping and e-commerce site. On the other hand, some plugins like Jetpack are essential for every type of site. So, prior to installing any plugin, do read its description and the main features.

Essential FREE WordPress Plugins

Jetpack by WordPress.com

Jetpack by WordPress.com is by far one of the most used WordPress Plugins out there when talked about security, performance, and site management.

Main Features of Jetpack

The main features of the Jetpack WordPress Plugin are:

• Brute-force attack protection, spam filtering, and downtime monitoring.
• Backups of your entire site, either once daily or in real-time.
• Secure login, with optional two-factor authentication.
• Malware scanning, code scanning, and automated threat resolution.
• Lazy image loading for a faster mobile experience.
• Advanced site stats and analytics for understanding your audience.
• Simple PayPal payment buttons for selling products and services.
• SEO tools for Google, Bing, Twitter, Facebook, and WordPress.com to maximize your reach.

[VIDEO TUTORIAL] Jetpack Plugin for WordPress (Step-By-Step) [Urdu/Hindi]

Yoast SEO

Yoast SEO is the most reliable WordPress plugin when talked about Search Engine Optimization. We know content is king, that’s why Yoast SEO is famous for its readability analysis and its SEO analysis.

Main Features of Yoast SEO

Following are the main features of Yoast SEO WordPress Plugin (free version):

• Automatically set canonical URLs to avoid duplicate content.
• The SEO analysis is an amazing tool to write SEO-friendly texts with the right (focus) keywords in mind.
• The readability analysis makes sure that you are writing easy-to-digest, engaging content for both visitors and search engines.
• Advanced XML Sitemaps functionality.
• The Snippet Preview shows you how your post or page will look in the search results.
• Gives you cornerstone content and internal linking features to help you rank for the right keywords with the right pages.
• Has a bulk editor so you can make large-scale edits to the titles and meta descriptions of your website.
• Translates your content to structured data where possible to help search engines understand your website.

The Premium version offers the following additional options:

• It gives you the option to have synonyms and related keyphrases.
• A redirect manager that helps you prevent 404 Page Not Found errors.
• Internal linking suggestions while you write.
• Write more natural with our automatic recognition of word forms
• Cornerstone content checks to point search engines to your main pages.

[VIDEO TUTORIAL] Yoast SEO Plugin Complete Setup [Urdu/Hindi]

Site Kit by Google

Site Kit by Google is a new player in the game. Site Kit is the official WordPress plugin from Google for insights about how people find and use your site. It provides authoritative, up-to-date insights from multiple Google products directly on the WordPress dashboard for easy access, all for free.

Main Features of Site Kit

The main features of Site Kit Plugin are:

• Easy-to-understand official stats from multiple Google tools directly on your WordPress dashboard.
• Metrics for your entire site and for individual posts
• Easy-to-manage, granular permissions across WordPress and different Google products.

Site Kit shows key metrics and insights from different Google products:

• Search Console: Understand how Google Search discovers and displays your pages in Google Search. Track how many people saw your site in search results, and what query they used to search for your site.
• Analytics: Explore how users navigate your site and track goals you’ve set up for your users to complete.
• AdSense: Keep track of how much your site is earning you.
• PageSpeed Insights: See how your pages perform compared to other real-world sites. Improve performance with actionable tips from PageSpeed Insights.
• Tag Manager: Use Site Kit to easily set up Tag Manager- no code editing required. Then, manage your tags in Tag Manager.

[VIDEO TUTORIAL] Google Site Kit Setup and Importance [Urdu/Hindi]

Health Check & Troubleshooting

Health Check & Troubleshooting performs a number of checks on your WordPress installation to detect common configuration errors and known issues, and also allows plugins and themes to add their own checks.

Main Features of Health Check & Troubleshooting

Following are the main Features of Health Check & Troubleshooting:

• Troubleshooting allows you to have a clean WordPress session, where all plugins are disabled, and a default theme is used, but only for your use until you disable it or log out.
• The Tools section allows you to check that WordPress files have not been tampered with, that emails can be sent, and if your plugins are compatible with any PHP version updates in the future.

[VIDEO TUTORIAL] Site Health Check & Troubleshooting (Theme/Plugin Conflict) [Urdu/Hindi]

Insert Headers and Footers

Insert Headers and Footers is a simple plugin that lets you insert code like Google Analytics, Google AdSense, Affiliate codes, Custom CSS, and more to your WordPress site header and footer. No need to edit your theme files!

Main Features of Insert Headers and Footers

Following are the main features of Insert Headers and Footers:

• The simple interface gives you one place where you can insert scripts, rather than dealing with different plugins.
• It is quick to set up, simple to insert scripts, insert header code and/or footer code.
• Add Google Analytics/AdSense code to any theme.
• Add custom CSS across themes.
• Insert any code or script, including HTML and Javascript.

Easy Table of Contents

Easy Table of Contents allows you to insert a table of contents into your posts and pages.

Main Features of Easy Table of Contents

Main features of Easy Table of Contents WordPress Plugin are:

• Automatically (optionally) generates a table of contents for your posts, pages and custom post types by parsing its contents for Headers.
• Many options are available to configure how the inserted table of contents appears which include several builtin themes.
• If the supplied themes do no meet your needs, you can create your own by choosing your own colours for the border, background and link colour.
• Multiple counter bullet formats to choose from; none, decimal, numeric and roman.
• Choose to display the table of contents hierarchical or not. This means headings of lower priority will be nested under headings of higher priority.
• User can optionally hide the table of contents. You full control of this feature. It can be disabled and you can choose to have it hidden by default.
• Supports smooth scrolling.
• Selectively enable or disable the table of contents on a post by post basis.
• Choose which headings are used to generate the table of contents. This too can be set on a post by post basis.
• Easily exclude headers globally and on a post by post basis.
• If you rather not insert the table of contents in the post content, you can use the supplied widget and place the table of contents in your theme’s sidebar.
• The widgets support being affixed or stuck on the page so it is always visible as you scroll down the page.
• The widget auto highlights the sections currently visible on the page. The highlight colour is configurable.

WordPress Download Manager

WordPress Download Manager is a Files / Documents management plugin to manage, track and control file downloads from your WordPress Site.

You can use Passwords, user roles to control access to your files, control downloads by speed or by putting a limit on download count per user, block bots or unwanted users or spammers using Captcha Lock or IP Block feature, you may also ask users to agree with your terms and conditions before they download.

Also, you may use the WordPress Download Manager as a complete e-Commerce Solution for selling digital products. Simply put a price when you need to sell a digital item.

You also may use license ( ex: Simple, Extended, Unlimited ) based prices for a product. Users can directly download free items and when an item has a price user will have to go through cart & checkout.

WordPress Download Manager has the easiest checkout option to give the user better experience in purchasing an item and which always increase the probability of successful completion of an order.

Main Features of WordPress Download Manager

Following are the main features of WordPress Download Manager:

• Adding a download is just like creating a post.
• Drag and Drop File Upload.
• Google Drive support to store your files in Google Drive (15 GB of space for free).
• DropBox support to store your files in DropBox (2 GB of space for free).
• Box.com support to store your files in Box.com (10 GB of space for free).
• OneDrive support to store your files in onedrive.live.com (15 GB of space for free).
• Option to “Open in Browser” or “Download” files (PDFs or images).
• Control who can access to download.
• Category level access control.
• Download speed control.
• Password and CAPTCHA protection.
• IP block option to prevent bot downloads or downloads from unwanted IP addresses.
• Download logs to check who is downloading which file from where and when.
• Terms protection – Agree with Terms & Conditions before download.
• Download counter to see total download count for each file.
• Custom download link icon and File type icon support.
• Custom front-end login / signup form shortcode
• Custom Embed template
• Searching and Sorting Option
• Widget for new files, top downloads, searching downloads
• Multi-level Categories
• Custom TinyMCE Button
• MP4 video upload and play support
• Video file download protection, allow visitors to play but block download

SM YouTube Subscribe

WP Last Modified Info

The key to successful blogging is by updating your older posts. By updating your previous posts you not only maintain their rankings but also rank further higher in search engines. Here is the complete guide of how you can rank your older posts.

Most WordPress themes usually show the date when a post was last published. This is fine for most blogs and static websites.

However, WordPress is also used by websites where old articles are regularly updated. This last updated date and time is important information for those publications. The most common example is news websites.

They often update old stories to show new developments, add corrections, or media files. If they only added the published date, then their users would miss those updates.

WP Last Modified Info WordPress plugin adds last modified/updated info on your WordPress posts and pages.

Main Features of WP Last Modified Info

The main features of WP Last Modified Info are:

• This plugin automatically inserts last modified or updated info on your WordPress posts (including custom post types) and pages.
• This plugin also adds ‘dateModified’ schema markup in WordPress posts automatically and it is used to tell the last modified date & time of a post or a page to various search engines like Google, Bing etc.
• Provides you with options to display the last modified/last updated date above or below your posts and pages.
• Allows you to customize the text which is to be displayed alongside the last modified date (default: Last updated on).
• Inserts ‘dateModified’ schema markup to your WordPress posts automatically.
• Displays last modified info on all post types column and publish meta box in the dashboard with the author name.
• Allows you to sort posts/pages in last updated/modified date-time order.
• Allows you to replace post published date with post modified info.
• Allows you to display last modified info on your post as human-readable format, i.e. Days/weeks/months/years ago.
• Allows you to display last modified info of all posts in the WordPress admin bar.
• Allows you to display last modified author info in posts, pages.
• Allows you to add last modified timestamp in post/page’s custom field.
• Allows you to edit last modified date and time from the post edit screen and quick edit screen as well.
• Send Email Notification when anyone makes changes to any post of your website.
• Tested with Yoast SEO, Rank Math, All in One SEO Pack, SEOPress, Schema and many other plugins.

Broken Link Checker

Broken Link Checker will monitor your blog looking for broken links and let you know if any are found.

Main Features of Broken Link Checker

The main features of the Broken Link Checker Plugin are as under:

• Monitors links in your posts, pages, comments, the blogroll (bookmarks), and custom fields (optional).
• Detects links that don’t work, missing images and redirects.
• Notifies you either via the Dashboard or by email.
• Makes broken links display differently in posts (optional).
• Prevents search engines from following broken links (optional).
• You can search and filter links by URL, anchor text and so on.
• Links can be edited directly from the plugin’s page, without manually updating each post.
• “Edit URL” lets you change the URL of that link. If the link is present in more than one place (e.g. both in a post and in the blogroll), all occurrences of that URL will be changed.
• “Unlink” removes the link but leaves the link text intact.
• “Not broken” lets you manually mark a “broken” link as working. This is useful if you know it was incorrectly detected as broken due to a network glitch or a bug. The marked link will still be checked periodically, but the plugin won’t consider it broken unless it gets a new result.
• “Dismiss” hides the link from the “Broken Links” and “Redirects” views. It will still be checked as normal and get the normal link styles (e.g. a strike-through effect for broken links), but won’t be reported again unless its status changes. Useful if you want to acknowledge a link as broken/redirected and just leave as it is.

Redirection

Redirection is the most popular redirect manager for WordPress. With it, you can easily manage 301 redirections, keep track of 404 errors. This can help reduce errors and improve your site ranking.

Main Features of Redirection

Redirection WordPress Plugins has the following main features:

• Create and manage redirects quickly and easily (without needing Apache or Nginx knowledge).
• It can be configured to monitor when a post or page permalinks are changed and automatically create a redirect to the new URL.
• A configurable logging option allows viewing all redirects occurring on your site, including information about the visitor, the browser used, and the referrer.
• A ‘hit’ count is maintained for each redirect so you can see if a URL is being used.
• The Redirection will keep track of all 404 errors that occur on your site, allowing you to track down and fix problems.
• Errors can be grouped to show where you should focus your attention and can be redirected in bulk.
• Import and export to CSV for viewing in a spreadsheet.
• You can also import from the following plugins:
  • Simple 301 Redirects
  • SEO Redirection
  • Safe Redirect Manager
  • Rank Math
  • WordPress old slug redirects

Google XML Sitemaps

Google XML Sitemaps improves SEO to create special XML sitemaps which helps search engines like Google, Bing, Yahoo and Ask.com to better index your site.

Main Features of Google XML Sitemaps

The main features of Google XML Sitemaps are as under:

• With such a sitemap, it’s much easier for the crawlers to see the complete structure of your site and retrieve it more efficiently.
• The plugin supports all kinds of WordPress generated pages as well as custom URLs.
• Additionally, it notifies all major search engines every time you create a post about the new content.
• Supported since over 9 years and rated as the best WordPress plugin, it will do exactly what it’s supposed to do – providing a complete XML sitemap for search engines.

W3 Total Cache

W3 Total Cache improves the SEO and user experience of your site by increasing website performance, reducing load times via features like content delivery network (CDN) integration.

Main Features of W3 Total Cache

These are the highlighted features of W3 Total Cache WordPress plugins:

• Improve the user experience for your readers without having to change WordPress, your theme, your plugins or how you produce your content.
• Improvements in search engine result page rankings, especially for mobile-friendly websites and sites that use SSL.
• At least 10x improvement (as per the developers) in overall site performance (Grade A in WebPagetest or significant Google Page Speed improvements) when fully configured.
• Improved conversion rates and site performance.
• Instant repeat page views: browser caching.
• Optimized progressive render: pages start rendering quickly and can be interacted with more quickly.
• Reduced page load time: increased visitor time on site; visitors view more pages.
• Improved web server performance; sustain high traffic periods.
• Up to 80% bandwidth savings via minify and HTTP compression of HTML, CSS, JavaScript and feeds.
• Compatible with shared hosting, virtual private/dedicated servers and dedicated servers/clusters.
• Transparent content delivery network (CDN) management with Media Library, theme files and WordPress itself.
• Mobile support: respective caching of pages by referrer or groups of user agents including theme switching for groups of referrers or user agents.
• Accelerated Mobile Pages (AMP) support and Secure Socket Layer (SSL) support.
• Caching of feeds (site, categories, tags, comments, search results) in memory or on disk or on CDN.
• Caching of search results pages (i.e. URIs with query string variables) in memory or on disk.
• Caching statistics for performance insights.

Akismet Anti-Spam

Akismet Anti-Spam checks your comments and contact form submissions to prevent your site from publishing malicious content. You can review the comment spam it catches on your blog’s “Comments” admin screen.

Main Features of Akismet Anti-Spam

Main Features of Akismet Anti-Spam include:

• Automatically checks all comments and filters out the ones that look like spam.
• Each comment has a status history, so you can easily see which comments were caught or cleared by Akismet and which were spammed or unspammed by a moderator.
• URLs are shown in the comment body to reveal hidden or misleading links.
• Moderators can see the number of approved comments for each user.
• A discard feature that outright blocks the worst spam, saving you disk space and speeding up your site.

Smush – Compress, Optimize and Lazy Load Images

Smush – Compress, Optimize and Lazy Load Images, as the name shows, optimizes your images turns on lazy load, resizes, compresses and improves your Google Page Speed with the incredibly powerful and free WordPress image smusher.

Main Features of Smush – Compress, Optimize and Lazy Load Images

These are some of the amazing features of Smush – Compress, Optimize and Lazy Load Images:

• Lossless Compression – Strip unused data without affecting image quality
• Lazy Load – Defer offscreen images with the flip of a switch
• Bulk Smush – Optimize up to 50 images with one click
• Image Resizing – Set a max width and height and large images will scale down as they are being compressed
• Incorrect Size Image Detection – Quickly locate images that are slowing down your site
• Directory Smush – Optimize images even if they are not located in the media library
• Automated Optimization – Asynchronously auto-smush your attachments for super fast compression on upload
• Unlimited & Free – Optimize all of your images up to 5MB in size forever (no daily, monthly, or annual caps)
• Gutenberg Block Integration – View all Smush stats directly in image blocks
• Multisite Compatible – Both global and individual Multisite settings
• Process All Your Files – Smush will process PNG, JPEG and GIF files for optimum results
• Super Servers – Smush images with no slowdown using WPMU DEV’s fast, reliable Smush API
• Convert to WebP (Pro Only) – Upgrade and automatically serve images in Next-Gen WebP
• Smush scans every image you upload – or have already added to your site – cuts all the unnecessary data and scales it for you before adding it to your media library.

VaultPress

VaultPress is a real-time backup and security scanning service.

Main Features of VaultPress

These are the highlighted features of VaultPress WordPress plugin:

• VaultPress is now powered by Jetpack and effortlessly backs up every post, comment, media file, revision, and dashboard setting on your site to our servers.
• With VaultPress you’re protected against hackers, malware, accidental damage, and host outages.

Contact Form, Drag and Drop Form Builder for WordPress – Everest Forms

Contact Form, Drag and Drop Form Builder for WordPress – Everest Forms provides you with an easy way to create any kind of forms including contact forms. Drag and Drop fields make ordering and creating forms so easy that even a beginner to WordPress can create beautiful forms within minutes.

Main Features of Contact Form, Drag and Drop Form Builder for WordPress – Everest Forms

These are the highlighted features:

• Create unlimited forms without any restrictions
• Drag and Drop Form fields
• Supports all commonly used form fields including radio, dropdowns, checkboxes, date and more
• 100% responsive form template
• Supports multiple-column layouts
• Multiple email recipient and multiple email notifications
• Smart Tags for a dynamic email message, subject and more.
• Quick Form Preview option
• CSV exporter for entries
• Provides two different forms of template design
• Google Recaptcha V2 and V3 Supported
• Spam protection via honeypot
• Editable successful form submission message
• Redirect option after submission
• Editable Email Settings
• Editable form validation message

User Registration – Custom Registration Form, Login And User Profile For WordPress

User Registration – Custom Registration Form, Login And User Profile For WordPress provide you with an easy way to create frontend user registration form and login form. Drag and Drop fields make ordering and creating forms extremely easy. The plugin is lightweight, extendible, and can be used to create any type of registration form.

It supports beautiful frontend profile account page for profile edit, password change, Log out and more. Users can visit their account page after registration and view the details they have filled and can make changes if necessary.

Main Features of User Registration – Custom Registration Form, Login And User Profile For WordPress

User Registration – Custom Registration Form, Login And User Profile For WordPress plugin has the following main features:

• Simple, Clean and Beautiful WordPress Registration Forms
• Drag and Drop Fields
• Unlimited Registration Forms
• Inbuilt Login Form
• Frontend Profile account page
• Multiple Column Design
• Multiple Form template designs
• Shortcode Support
• Google ReCaptcha Support (v2 and v3)
• Email notifications and Email Customizers
• Form Duplicate Option
• Admin approval option for registration
• Auto-login option
• An email confirmation to register
• Enable/Disable Strong Password
• Default User Role Selection Option
• Support for profile image upload
• Form Preview Option on the backend
• User data export in CSV
• Import/Export registration form

WooCommerce

WooCommerce is a flexible, open-source eCommerce solution built on WordPress. Whether you’re launching a business, taking an existing store online, or designing sites for clients you can get started quickly and build exactly the store you want.

WooCommerce is developed and supported by Automattic, the creators of Jetpack and WordPress.com, along with independent contributors. 

Main Features of WooCommerce

WooCommerce WordPress plugin is among the top E-commerce plugins. It has amazing options to use on a site. Some of these are as under:

• Product, Cart, and Checkout pages
• WooCommerce comes bundled with the ability to accept major credit cards, alternative payment methods, BACS (bank transfers), and cash on delivery.
• Configurable shipping options, including flat rates and label printing
• Integrate content and commerce across your site via modular blocks
• Automated tax calculations. WooCommerce gives you complete control – from taxes to stock levels to customer accounts.
• Google Analytics, MailChimp, and Facebook integration
• Central store dashboard with key metrics, and more.
• There is also a free WooCommerce mobile app (Android and iOS) for store management on the go.
• Using this you can sell both physical and digital goods in all shapes and sizes, offer product variations, complex configurations, and instant downloads to shoppers; and even sell affiliate goods from online marketplaces.
• Shipping with WooCommerce is highly configurable. Adjust the built-in settings to offer free shipping or flat rate shipping, limit your shipments to specific countries by setting up shipping zones, or open your store up to the world.

WP Social Icons

WP Social Icons is a simple, lightweight plugin which allows you to easily add different social font icons on your site. 

This plugin has easy to use configuration, which allows you to add your different social network accounts, customize look and feel of the plugin to match your site design.

Main Features of WP Social Icons

WP Social Icons has the following cool features:

• The plugin has a collection of 260 font icons to choose from.
• You can easily put the social icons to your post/page/sidebar/header/footer etc.
• Easily change the color of icons to match your website look and feel.
• Fully responsive front end.
• Easy to use admin interface.
• Easily add any social network based on the icons.
• Uses shortcode to display your social icons on your site and in widgets.

Slider by Nivo – Responsive WordPress Image Slider

Slider by Nivo – Responsive WordPress Image Slider is among the worlds most popular jquery image slider plugin.

Main Features of Slider by Nivo – Responsive WordPress Image Slider

Slider by Nivo – Responsive WordPress Image Slider plugin has the following top features:

• It lets you easily create a post slider, an image carousel or a slideshow.
• Create sliders from Galleries, Categories and Sticky Posts
• More custom themes
• Build carousels.
• Upcoming lightboxes support.

Schema – All in One Schema Rich Snippets

Schema – All in One Schema Rich Snippets easy implementation of schema types like Review, Events, Recipes, Article, Products, Services etc.

Main Features of Schema – All in One Schema Rich Snippets

These are the main features of Schema – All in One Schema Rich Snippets WordPress plugin:

• It gives search engines only the important & precise information to display in search result snippets.
• Rich Snippets are very interactive (photos, star ratings, price, author, etc.) to let you stand out from the competition.
• Helps you rank higher in search results.
• Helps Facebook display proper information when users share your links on Facebook.
• This plugin supports the following types of Schemas:
  • * Review
  • * Event
  • * People
  • * Product
  • * Recipe
  • * Software Application
  • * Video
  • * Articles

CSS & JavaScript Toolbox

CSS & JavaScript Toolbox(CJT) adds and manages CSS, JavaScript, HTML and PHP code to unique CJT Code Blocks and assigns them anywhere on your website.

Main Features of CSS & JavaScript Toolbox

CSS & JavaScript Toolbox has the following important features:

• Add CSS, JavaScript, PHP and HTML to Pages, Posts, Custom Posts, Tags, Categories, URLs, Regex and much more.
• Add front-end styles without modifying your Theme files.
• Add functionality without the core file hacks or custom plugins.
• Embed scripts from GitHub, Code Canyon, JSFiddle, etc.
• Add visitor tracking, advertising and affiliate scripts.
• Embed social media channels or marketplace store widgets.
• Streamline your website development – whether solo or in a team.
• No need for FTP – just add your code, click save, see the change.

Contact Form 7

Contact Form 7 can manage multiple contact forms, plus you can customize the form and the mail contents flexibly with simple markup.

Main Features of Contact Form 7

The highlighted features of Contact Form 7 WordPress plugin are as under:

• The form supports Ajax-powered submitting, CAPTCHA, Akismet spam filtering and so on.
• With the default configuration, this plugin, in itself, does not:
  • track users by stealth;
  • write any user personal data to the database;
  • send any data to external servers;
  • use cookies.

[VIDEO] Essential Free WordPress Plugins (20+) [Urdu/Hindi]

VIDEO TIMESTAMPS:

• [01:10] How to Install a Plugin?
• [03:44] Jetpack by WordPress.com
• [05:18] Yoast SEO
• [06:30] Site Kit by Google
• [07:32] Health Check & Troubleshooting
• [09:12] Insert Headers and Footers
• [10:26] Easy Table of Contents
• [12:07] WordPress Download Manager
• [13:48] SM YouTube Subscribe
• [14:50] WP Last Modified Info
• [16:14] Broken Link Checker
• [17:04] Redirection
• [17:52] Google XML Sitemaps
• [19:04] W3 Total Cache
• [20:15] Akismet Anti-Spam
• [21:11] Smush – Compress, Optimize and Lazy Load Images
• [22:30] VaultPress
• [23:10] Contact Form – Drag and Drop Form Builder for WordPress – Everest Forms
• [23:48] User Registration – Custom Registration Form, Login and User Profile for WordPress
• [24:45] WooCommerce
• [25:43] WP Social Icons
• [27:11] Slider by Nivo – Responsive WordPress Image Slider
• [28:28] Schema – All in One Schema Rich Snippets
• [29:30] CSS & JavaScript Toolbox
• [30:25] Contact Form 7

Let us in comments below which one you consider is the best free WordPress Plugins out there. Also, add the missing ones you consider are essential for any site.