Sometime we have errors in the links because of change in url locations and sometimes referring links in the posts floats “404 errors”. We also have possibilities that Wikipedia images used in our posts may be deleted, linking sites in the posts may expire or may stop working. All these errors comes under observations when you have an eye over the response of all the urls associated with your blogs. It is quite impossible to check all the links manually if you have more than 1000 posts in your blogs.
Broken Link Checker is a WordPress plugin which automatically checks all the post and pages for errors in links and images. It will auto notify about the errors at the WordPress Dashboard. This plugin checks for the errors within defined interval of time(you can change the time interval from the plugin options)