Hatena Block is a free Chrome add-on developed by Orangesoft Inc. It falls under the category of Browsers and is specifically designed as an add-on for Hatena Bookmarks. The main purpose of this add-on is to filter and hide articles on Hatena Bookmarks based on their titles or URLs.

With Hatena Block, users can easily block specific websites or articles that they do not wish to see on Hatena Bookmarks. By registering the titles or URLs of the articles they want to hide, users can effectively filter out unwanted content and have a more personalized browsing experience on the platform.

Overall, Hatena Block is a useful tool for Hatena Bookmarks users who want to have more control over the content they see. Its simple and straightforward interface makes it easy to use, and its free license makes it accessible to all Chrome users.