SiteBlock is a free Chrome extension developed by Costa that allows users to block websites in order to discourage procrastination. This extension is especially useful for individuals who find themselves visiting unrelated websites while trying to focus on a specific task.

With SiteBlock, users can easily set a list of sites to block through the Extension Options. To access the options, simply navigate to the Chrome menu, then go to More Tools -> Extensions -> SiteBlock -> Details -> Extension Options. From there, users can input the websites they wish to block and effectively create a barrier to prevent themselves from accessing those sites.

Overall, SiteBlock provides a simple and effective solution for those who struggle with staying focused and avoiding distractions online. By blocking specific websites, users can increase their productivity and reduce time spent on irrelevant web browsing.