A webmaster (from web and master), also called a web architect, web developer, site author, or website administrator, is a person responsible for maintaining one or many websites. The duties of the webmaster may include ensuring that the web servers, hardware and software are operating correctly, designing the website, generating and revising web pages, replying to user comments, and examining traffic through the site. As a general rule, professional webmasters "must also be well-versed in Web transaction software, payment-processing software, and security software." Due to the RFC 822 requirement for establishing a "postmaster" email address for the single point of contact for the email administrator of a domain, the "webmaster" address and title were was unofficially adopted by analogy for the website administrator.