# Effective Techniques for Protecting the Privacy of Web Users
## 2 Related Study  
A recent and comprehensive overview of the web-tracking domain and guidelines for future studies by outlining the methodologies and importance of the web-tracking field are discussed in [PERSON] et al. [3].  
Similarly, a detailed overview in [PERSON] and [PERSON] [4] by outlining potential privacy issues, providing possible tracking mechanisms that could be exploited, and presenting the available privacy-preserving tools with their strengths and weaknesses.  
In recent years, several studies [5; 6; 7] have addressed the privacy implications of third-party tracking on the web through an analysis of trackers used on each website. Other studies have discussed the existing tracking strategies used by third-party services in order to create profiles of users and track their online activities. Their findings indicate that trackers are widespread as expected, and the web is dominated by Google, Facebook, and Twitter.  
Some research studies [1; 8; 9; 10] have examined and assessed the performance of existing privacy-protection tools.  
[PERSON] and [PERSON] [11] analyzed the Ghostery interface, which serves as a privacy protection tool for blocking third-party tracking on websites. The analysis method includes reviewing the extensions' usage and execution and then performing a heuristic analysis of the extension's interface. The findings indicate that researchers do not have any difficulties using Ghostery since they are familiar with it. However, unfamiliar users are unable to experience the full benefits of this extension. Therefore, as a way of easily mitigating privacy breaches, privacy tools must offer a user-friendly interface.  
Likewise, the study by [PERSON] et al. [1] evaluated the performance of five privacy protection tools by measuring their output based on a set of manually labeled JavaScript programs obtained from different domains. The results suggest that existing PPTs need to be substantially improved in order to achieve an optimal balance between true and false positives.  
In addition, [PERSON] et al. [9] conducted a qualitative and quantitative analysis to assess the effectiveness of privacy protection tools in terms of filtering unwanted content, hardware resource consumption, and mean response time. According to the results, existing PPTs are consuming more RAM (Random Access Memory) as they need to maintain the files with resources in the main memory to be able to block them. Due to this, performance seems to be a critical issue considering the high consumption of system resources. Moreover, all existing PPTs mainly utilize blacklists to remove unwanted content. Thus, they do not effectively block web tracking since blacklists need to be constantly updated and maintained by end users.  
Moreover, [PERSON] et al. [10] study the behavior of ad-blocking extensions on different websites, evaluate the advantages of using these extensions and examine how they increase traffic. The result shows that ad-blocking extensions can prevent displaying ads on websites by blocking third-party services and disabling them from being stored on the user's device. However, blocking all third-party services can cause functionality loss on webpages if third-party images, JavaScript programs, or flash files are not loaded.  
Also, [PERSON] et al. [8] Analyze the efficiency of various tracker blockers in terms of their impact on web quality of experience (QoE) and protection against third-party tracking by generating traffic automatically.  
In agreement with our findings, most of the above works also find that current privacy protection tools do not effectively protect against web tracking, cause performance issues, and are difficult to use by end users. Finally, we note that our study on analysing the effectiveness of PPTs is complementary to prior research on their effect on page load time and determining the suitable balance between allowing and blocking web tracking as in [18].