Adam Greenberg provides an excellent overview of Exploit Kits. If your computer is running windows, visiting an infected forum could result in a redirect to the Fiesta Exploit Kit. A redirect is a key to creating harmful magic exploitation tricks. Its job is simple. The redirect sends the hapless user to site filled with malicious language code. The landing page is the culprit the launches the harmful exploits. Without a redirect, there would be no traffic going to the page.
Most people don’t realize that when a major website has been compromised, it means that someone hacked the site and placed a redirect link on the hacked page. The “redirect” sends a small part of the hacked page, called a frame, to the landing page that performs the actual attack. To the user, the page they land on appears to be normal.
An attacker’s desire to draw traffic to a malicious landing page is the same desire that any marketer has to draw traffic to their website. The attacker’s act of generating traffic is divided into campaigns, which are just like any marketing campaign. The links that direct people to the malicious page have identifiers and allow the hacker to determine which technique was used to generate the traffic.