A plug-in is a piece of software that adds new features or extends functionality on an existing application. Commonly used on websites that are built with content management systems - like BigCommerce, WordPress, Jooomla! and Drupal - plug-ins serve many useful purposes for business owners and website visitors. They can create new functionality, improve speed and efficiency, and maximize user experience while requiring minimal effort from webmasters.


In the early years of the Internet, websites offered visitors a very limited experience. Most couldn't deliver more than simple text, a couple still images and links. Plug-ins were invented to overcome the limitations of early HyperText Markup Language (HTML), the standard coding language programmers use to create webpages (1). They helped create a more engaging presentation for site visitors. Since then, plug-in usage has exploded. There are thousands of plug-ins that people can easily install and use on their websites.

How plug-ins work

Plug-ins serve a purpose that is specifically defined. They specialize in processing specific types of content and integrating it into the platform, often blending seamlessly into the user interface. Even though plug-ins sometimes look like part of the website itself, the platform operates independently of them. This allows webmasters to update plug-ins without having to worry about creating changes on the host application. Developers use application programming interfaces (APIs), which allow plug-ins to interact with the website, and if the API is stable, a plug-in will continue to run as the original version is modified (2).


Over the years, developers have created plug-ins that cover a wide variety of needs for website owners. The most popular BigCommerce plug-ins help webmasters do everything from track their SEO campaigns (Google Analytics) to sending marketing material (Constant Contact and MailChimp) or shipping orders (ShipStation) - all without having to jump between different applications.


The main advantage of using plug-ins is the ability to expand the functionality of your website quickly and easily. Webmasters can usually download and install them within minutes. Developers also update plug-ins frequently, sometimes several times year, as they make performance and security improvements. When these updates occur, webmasters will usually see a prompt to update the program when they log in to the website CMS dashboard.


When a website owner downloads and installs a plug-in, they are at the mercy of the third-party developer that created the program. Some plug-ins are top notch and function exactly as described, while others are buggy, out of date, or file-heavy, or they lack security.

  1. Security problems - CMS platforms like WordPress are widely regarded to be very secure at their core, but when external sources - like plug-ins - are invited in, security can be compromised and leave the website vulnerable to hacking. Even some of the most popular WordPress plug-ins, such as W3 Total Cache, have suffered security flaws in the past (3).
  2. Drain on resources - Every plugin you install adds "weight" to your website. Plug-ins consume processing power which can slow down your website and even cause it crash.
  3. Conflicts - Sometimes plug-ins react badly with certain websites. They can clash with a CMS, website theme or even other plug-ins, particularly after the user processes an update.
  4. Dependability - Relying on third-party developers always involves risk. You may experience problems operating the plug-in and find it difficult or impossible to get a response from the people who created it.

Paid versus free plug-ins

Thousands of free plug-ins are available for download and many are highly regarded in the Web development community. However, free plug-ins usually don't offer much support to the user. Developers of paid plug-ins are more invested in providing good customer service and try to keep the programs bug-free and compatible with the CMS they were designed for.

Plug-ins are invaluable tools for webmasters and site visitors alike. They can add entirely new dimensions to a website, improving its operation and expanding the features it offers. They are so easy to install and use that webmasters often download them without considering the potential negative impacts. You should be judicious about which plug-ins you use and how many. Try to limit them as much as possible to avoid potential conflicts and bloat, and make sure you read reviews of any plug-in you are thinking of using. Researching options carefully before hand can prevent disastrous consequences down the road.

1. 20 things I learned about browsers & the web
2. What are plug-ins and its pros and cons
3.The Dangers of WordPress Plugins Ignorance (And What To Do About It)

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