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A add-on is an additional program or module that complements browsers, mail programs and other software and hardware apps and adds functions that the basic system does not have. As an extension for software and hardware, the add-on changes several characteristics of the system in which it is implemented, thus increasing the range of functions. For example, add-ons can increase security, provide analytics, manage data, or prevent script execution. The possible apps are very diverse.

General information

Unlike a plug-in, an add-on it is not independent in its range of functions. The add-on extends the basic functions and provides a special feature for the system (client, browser, application). The basic system program code forms the basis of the add-on, which is logically linked to the code via interfaces (APIs) and software libraries. Add-on programs access these resources, while plug-ins provide their own resources and are independent.

Ass-ons are customized using SDKs (Software Development Kit) for the particular system, so that they can be added later via download. Most of the add-ons are provided by the creator of the basic system, such as the browser add-on to disable Google Analytics, or various thematic add-ons for Mozilla Firefox that change the look of this browser. Add-ons can also be offered by third parties, independent developers, or agencies, some of which are open systems and open source software. They are usually designed to handle special problems or tasks in the workflow.

How does it work

Most of the add-ons are available for apps, browsers, and games. The add-ons are offered for download as part of the software, which is intended to supplement and can be installed with a few clicks, in most cases free of charge. Add-ons can be divided into two categories:

  • Extensions: One or more tools are added to an existing program. These add-ons are often called browser extensions.
  • Individualization: Themes, templates and characters change the look and feel of the browser through optical adaptation of the graphical user interface.

For both versions, the add-on only adds functions. It always depends on the basic program to complement it. For this reason, system performance is often affected, since additional software is connected to the system at different points. Each add-on slows down the basic program to some extent (up to 10%) during a reboot, since interfaces are accessed and system functions are used. Extensive browser customizations are sometimes associated with a significant loss of performance.

At the same time, some add-ons can transfer personal data or prevent the basic software from transmitting data. On the one hand, data security and privacy can be established and expanded by means of add-ons, such as script blocking, trade promotion, and IP addresses. Apart from this, the add-ons can also transfer data without the user noticing. In principle, there is a risk of downloading malicious software with each download, especially with so-called software packages.

Before adding an add-on, you should first examine the legitimacy and reliability of the source and add-on provider to rule out any gaps in software security and prevent malware attacks. Even if these cases are rare, it is advisable to choose add-ons based on specific requirements and thus minimize potential risks. Manufacturers also offer mechanisms to verify software, digital rights management, and encryption methods for data transmission. When downloading an add-on, it is advisable to check precisely where the additional software is coming from, what it is doing, and what data it transmits in what way.

Relevance for online marketing

Numerous add-ons and browser extensions are offered for online marketing, search engine optimization or web analytics. They simplify workflows and perform special tasks. One of the most famous add-ons is the Technical Firebug. This developer tool can evaluate various items from a web portal and the underlying source code. You can review and examine layouts, CSS markup, redirects, and load times. Various add-ons are used to review backlinks, domain authorities or other KPIs. Scraping tools can get data and export it to tables, for example. Numerous add-ons currently exist including redirects, canonical URLs, user agents, notes, and mind maps. The add-ons are so many that even special add-ons that manage add-ons are on the market and are very practical.

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