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Plug-in refers to software apps that are programmed using interfaces to extend the functionality of other software.

How plug-ins work

If a software product is used by many people, there will soon be a great demand for additional features. In this way, more and more software vendors are building interfaces that allow programming new features and connecting with software. Therefore, a somewhat limited software is transformed into an all-rounder for the most diverse needs.

Difference between plugins and add-ons

The terms plugin and add-on are commonly used interchangeably. Regardless, this is strictly incorrect. A plugin is a duration of a software, which also can work without the actual main program. A plug-in, on the other hand, extends the software, but cannot run without it and is thus only useful in combination with the main program.

A classic example is browser plugins. Modern browsers like Mozilla Firefox, Google Chrome or Internet Explorer are designed so that they can be extended with add-ons at any time. Thus, for example, you can update your security, simplify bookmark management or search the web, and adjust the browser display.

Plugins for desktop software

There are plugins for certain image editing programs. Typical representatives of this category are Photoshop, Gimp, and IrfanView. Through a plugin, you can add graphic filters or complement the processing capacity for certain graphic formats, for example. In addition, vector graphics apps or 3D software are available. The plugins are also used in the following software products:

  • Email software (including calendar, contact management, security, language tools)
  • Media players (such as video and audio effects, decoders)
  • Sequencer programs (like software synthesizers and effects)
  • Audio editing software
  • Plugins for Internet software

Content management systems can be expanded almost infinitely through plugins. There are around 27,000 plugins available only for WordPress, Joomla or TYPO3 and they also have large directories of plugins. These extensions can perform the following functions, for example:

  • SEO features.
  • Fight against spam.
  • Creation of a site map.
  • Tracking of visitor data.
  • Online store functionality.
  • Galleries and slides.
  • Security / captcha inquiries.
  • Contact forms.
  • Link to social media services.

Open source store systems are also extended with plugins. Typical examples of module-based store systems are Magento, xt: Commerce, and Shopware. Software makers offer large markets with thousands or even hundreds of extensions which are provided in part by the manufacturer. Despite everything, many of these modules are programmed by third parties for free or for purchase.

Advantages and disadvantages of plugins

The advantage of plugins is clearly in the improved functionality without having to buy any additional software. These extensions they are generally free. The generally simple and especially automated installation is further advantageous. Access to the plug-in is done directly by navigating the main software.

Plugins can pose an obstacle when they are programmed by a third party and are available for download. For this case, there is usually no control over whether the specified functionality is provided without restrictions. Software cannot be guaranteed to be free of security vulnerabilities.

Relevance for SEO

For search engine optimization, plugins are important insofar as certain browsers, content management systems and store systems can be extended with SEO functionalities. With browser plugins and toolbars, important indicators such as visibility index or backlinks can be tracked. They help with keyword research, analyze source code, or display Whois information from a web portal.

In CMSs, plugins can help handle the most important optimization actions on a page, for example updating metadata, optimizing images, caching, and internal linking. Through the use of modules, the store systems can be extended with rich snippets, canonical tags, blog functions, sitemaps, friendly URLs and many more SEO functions. The plugins do not offer any information that cannot be obtained through other tools, but since they are usually free and take the latest information directly to the right place, they can greatly facilitate the work of optimizers from search engines.