Browser toolbar

A browser toolbar is a toolbar that resides within a browser's window. All major web browsers provide support to browser toolbar development as a way to extend the browser's GUI and functionality. Browser toolbars are considered to be a particular kind of browser extensions that present a toolbar. Browser toolbars are specific to each browser, which means that a toolbar working on a browser does not work on another one. All browser toolbars must be installed in the corresponding browser before they can be used, and require updates when new versions are released.

Many high-profile browser toolbars released over the years have been fraught with issues, either intentionally as malware or injected with computer viruses or due to poor or conflicting programming when considering multiple toolbars being included on the single browser.

Over the 2000s, there was a proliferation of browser add-ons produced and released by a variety of software companies, both large and small, which were designed to extend the browsing experience for the end user. Due to this popularity, and the ease with which users could have these installed, there was additionally an adoption by malware, adware and other privacy-invasive tracking tools. The popularity of browser toolbars has declined.

Many unscrupulous companies use software bundling to force users downloading one program to also install a browser toolbar, some of which invade the user's privacy by tracking their web history and search history online. Many antivirus companies refer to these programs as grayware or Potentially Unwanted Programs (PUPs).

The programming language and development tools behind a browser toolbar vary from one browser to another.

In Internet Explorer 5 or later toolbars may be created as browser extensions written in C# or C++. More specifically, it is possible to create up to three different kinds of toolbars (custom explorer bars, tool bands and desk bands) and to combine them with browser helper objects in order to provide added functionality.

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