A webmaster is a person responsible for maintaining one or more websites. The title may refer to web architects, web developers, site authors, website administrators, website owners, website coordinators, or website publishers.

The duties of a webmaster could include:

• Creating, editing, and publishing content on the website, either independently or with other content creators
• Content placement
• Managing a website's appearance, user access rights, and navigation
• Ensuring that the web servers, hardware and software are operating correctly
• A/B testing
• Analysing traffic through the site
• Ensuring the website is up to date and functioning correctly, e.g. installing updates, fixing bugs and errors, and optimizing performance
• Optimizing the website's content and structure to improve its ranking in search engines (SEO), e.g. keyword research, link building, and optimizing meta tags and titles
• Keeping the site secure, e.g. installing security software, monitoring for threats, and implementing practices for data protection
• Analytics, e.g. monitoring the website's traffic and performance to make informed decisions about its content
• Customer support, e.g. troubleshooting any issues that users may be experiencing.

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 unofficially adopted by analogy for the website administrator. RFC 2142, which turned this common practice into a standard.

Webmasters may be generalists with HTML expertise who manage most or all aspects of web operations. Depending on the nature of the websites they manage, webmasters may be required to know scripting languages such as ColdFusion, JavaScript, JSP, .NET, Perl, PHP, Python and Ruby.^{[citation needed]} They may also need to know how to configure web servers such as Apache and be a server administrator.^{[citation needed]} Most server roles, however, would be overseen by an IT Administrator.^{[citation needed]}