The role of a Webmaster is defined by Wikipedia as thus:

“The webmaster, also called the system administrator, the author, or the website administrator, is the person responsible for designing, developing, marketing, or maintaining a website.”

This is a good, but fairly general description of the role. The actual role will of course have infinite combinations of tasks depending on the type of websites(s) a Webmaster looks after, or the size and type of the business.
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