Very popular with Internet users use plug-ins designed for your email program. Is a user-configurable spam filters and plugins for automatic antivirus check of incoming mail.

Most plugins are provided by browser developers for free. Users can download from the manufacturer's website. And in the process of viewing pages in the Internet browser detects the absence of some plugins and the user will offer to install them automatically.

To install the plugin, for example, for the popular Mozilla Firefox browser, you must activate the icon on your desktop and run it. Then choose the menu "Tools" and "add-Ons". A new tab will open where you can either click on the "Search extensions", or enter the name of the desired plugin. The browser will display multiple types of plugins matching the search criteria.

Selecting from the offered, we need to confirm your choice. Click the button "add to Firefox". The browser will warn the user that need to install add-ons only from authors whom you trust. Under each of the plugins are statistics, allowing to estimate, how many people prefer to use plugins. To install on your computer users can choose from several plugins. If there is no doubt – enable the command "Install now".

When the addition (or additions) will be installed, Mozilla Firefox will prompt the user to restart the browser. Click "Restart Firefox".

If you install the plugin in a similar way failed, you can use a different method. Again, activate the tab "Tools", then "add-Ons" and then click "See all recommended add-ons". Mozilla Firefox automatically redirects the user to your website with apps, where you can choose any Supplement that is recommended by the developers of the browser. Choose the desired plugin and confirm the selection by pressing the button "add to Firefox" next to the application.

We just need to remember that every Supplement has its own range of versions browser support, which is called compatibility. This, too, should pay attention to, for example, if you specify compatibility with Firefox 1.5–3.0, then with later versions of the browser this add-on will not work. The same thing will happen when you upgrade Mozilla Firefox add-ons will stop working. The user will have their own upgrade to the required version.