External resources are externally added to a website, which means they don't belong to the website itself. Items such as plug-ins placed for performance analysis, advertising areas, videos from other websites, or social media buttons are examples of third-party resources. These elements can help the web page to be more dynamic and interactive. However, in some cases, the unnecessary or wrong use of resources may cause the relevant web page to load slowly as they mean extra codes and processes. Therefore, in order not to negatively affect the loading speed, it is recommended to remove unnecessary third-party resources.