Workplace Internet usage is a common problem for both employers and employees in the 21st century. As the Internet is required more and more for everyday work tasks, the opportunity to use the Internet for personal use while on the job has become common. Many employees browse websites, play online games, send personal emails, and engage in other personal online activity while at work. This can lead to a loss of productivity as more and more time is wasted on activities not related to work. There is also a risk to employers when their employees use the Internet; computer viruses and data loss or data theft are often a concern. Because of this, many employers have specific rules and regulations regarding workplace Internet usage. The policies vary by employer; some employers may be more lenient with regard to workplace Internet usage, while other employers make take a much stricter approach. Blocking and tracking programs are sometimes used by employers to monitor their employee's online activity.