The principle of operation of the plugins is the following. The application for which they are intended, provides them with services for their use. These services include features such as registration of the plug-in program and Protocol that allows to exchange information with other plugins. As a rule, without the services provided plugins are used very rarely, as they are dependent on them. In turn, the program allows users to add, remove, and update plugins without any changes to the application itself.Among the applications that provide the possibility of creating a plugin can be a program to edit images, audio and video, Internet browsers, media players, office applications etc. you can Also note the plugins for content management systems (CMS) such as Wordpress or Joomla.Plugin installation can be accomplished in several ways. For example, Internet browsers allow you to install a plugin providing your interface. In the special tab, open the repository with the plugins that are installed by clicking the appropriate buttons. For some programs, the installation of the plugins is accomplished by copying the relevant files in a dedicated folder of the program. When you run the application data directories are scanned for plugin files, and if available, connect to the application.For programs image-editing plug-ins can add functionality colour correction, any deformation, applying watermarks, etc. Quite often plug-ins allow programs to work with those file types that are not natively supported. In audio editors, plug-ins are used to create certain effects, distortion of sound, changes its characteristics. Especially popular are plug-ins for web browsers that can block ads and pop-UPS, to provide statistical information about the pages they visit, upload video files, etc.