Components

About Banners

Web banners, also called banner ads, are a common form of advertising on the web. Like real-world banners, they are usually displayed with a high aspect-ratio: narrow and tall or short and wide. Their purpose is to link back to the advertisers' websites to generate income for the hosting site.

Banners may be simple text and images. Or they may be multimedia objects designed to play animations and sounds to attract attention.

In banner terminology:

Impressions refer to the number of times the banner has been displayed.
Click-throughs refer to the number of times that users have clicked on the displayed banners.

The content provider on whose page the banner is displayed receives a small payment for each Impression and a more substantial payment for each Click-through. Often, the payments are used to cover the cost of running the host site.

If banners are too attention-grabbing, users become annoyed with them and employ an ad-blocker to prevent the display of banners.

More information

There is good coverage of the Banners component in its Help pages
On banners in Joomla: see this Magazine Article.
On banners in general: Wikipedia: Web banner.

Components are a type of Extension.

Components are the main functional units of Joomla! they can be seen as mini-applications. An easy analogy would be that Joomla! is the operating system and the components are desktop applications. The content of a component is usually displayed in the center of the main content area of a template (depending on the template).

Most components have two main parts: an administrator part and a site part. The site part is what is used to render pages of your site when they are requested by your site visitors during normal site operation. The administrator part provides an interface to configure and manage different aspects of the component and is accessible through the Joomla! administrator application.

Installing Components

Joomla! comes with a number of core components, like the content management system, contact forms and Banners. More components can be found in the Joomla! Extensions Directory. If you want to learn how to add a component to your Joomla! installation, read more about Installing an extension here.