Masking components such as BlockUI and Spotlight were introduced to make UIs more attractive and they were controlled by blocking a certain piece of the web page. BlockUI allows certain parts of a page to be blocked using Ajax calls and Spotlight is useful for restricting input to a specific element by masking other parts of the page.
BlockUI allows blocking any piece of a web page using Ajax calls and makes a transparent blocking layer over the target elements. BlockUI is initiated by the source component to block one or more target elements. You can block a certain part of a page or an entire page by following the convention of wrapping the
div element (