The General Data Protection Regulation (GDPR), which took effect on May 25, 2018, is a set of regulations governing the use of personal data across the EU. This is forcing some affiliates to obtain user data through opt-in consent (updated privacy policies and cookie notices), even if they are not located in the European Union. This new regulation should also remind you to follow FTC guidelines and clearly disclose that you receive affiliate commissions from your recommendations.
The implementation of affiliate marketing on the internet relies heavily on various techniques built into the design of many web-pages and websites, and the use of calls to external domains to track user actions (click tracking, Ad Sense) and to serve up content (advertising) to the user. Most of this activity adds time and is generally a nuisance to the casual web-surfer and is seen as visual clutter. Various countermeasures have evolved over time to prevent or eliminate the appearance of advertising when a web-page is rendered. Third party programs (Ad-Aware, Adblock Plus, Spybot, pop-up blockers, etc.) and particularly, the use of a comprehensive HOSTS file can effectively eliminate the visual clutter and the extra time and bandwidth needed to render many web pages. The use of specific entries in the HOSTS file to block these well-known and persistent marketing and click-tracking domains can also aid in reducing a system's exposure to malware by preventing the content of infected advertising or tracking servers to reach a user's web-browser.
Spam is the biggest threat to organic search engines, whose goal is to provide quality search results for keywords or phrases entered by their users. Google's PageRank algorithm update ("BigDaddy") in February 2006—the final stage of Google's major update ("Jagger") that began in mid-summer 2005—specifically targeted spamdexing with great success. This update thus enabled Google to remove a large amount of mostly computer-generated duplicate content from its index.