'HTTP Security Response Headers' allow a server to push additional security information to web browsers and govern how the web browsers and visitors are able to interact with your web application.
Having the appropriate Security Header Response policies in place adds another level of protection that can stop common attacks such as code injection, cross-site scripting attacks and clickjacking. For most CMS sites such as WordPress and hosts using Apache servers, these Header Response policies can be set via the .htaccess file.