Webmasters are generally the person(s) responsible for a website so that it is a mix of systems administrator and web developer.
Skills would include understanding at least one server software, e.g. Apache or Microsoft Internet Information Services, and some basic HTML skills. Now generally there should also be some server-side scripting/programming, e.g. PHP or ASP.Net, as well as possibly knowing some Javascript, CSS, XHTML, and how to configure a server.
To write all that I know would likely take almost a decade as it would be 33 years of memories in addition to the knowledge that I possess from living those years like remembering net
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