As a Webmaster, you will need to master following:

• apply ICT system usage policies
• graphics editor software
• implement front-end website design
• maintain ICT server
• maintain responsive design
• proxy servers
• troubleshoot website
• use markup languages
• use scripting programming
• use software libraries
• web programming

More generally, a webmaster is also versed in:

• apply tools for content development
• authoring software
• quality assurance methodologies
• study website behaviour patterns
• style sheet languages
• use ICT ticketing system

It also helps to know the following:

• ABAP
• AJAX
• APL
• ASP.NET
• Adobe Illustrator
• Adobe Photoshop
• Assembly (computer programming)
• C#
• C++
• COBOL
• CSS
• CoffeeScript
• Common Lisp
• Erlang
• GIMP (graphics editor software)
• Groovy
• Haskell
• ICT debugging tools
• ICT performance analysis methods
• ICT recovery techniques
• JSSS
• Java (computer programming)
• JavaScript
• LESS
• Lisp
• MATLAB
• ML (computer programming)
• Microsoft Visio
• Microsoft Visual C++
• Objective-C
• OpenEdge Advanced Business Language
• PHP
• Pascal (computer programming)
• Perl
• Prolog (computer programming)
• Python (computer programming)
• R
• Ruby (computer programming)
• SAP R3
• SAS language
• Sass
• Scala
• Scratch (computer programming)
• SketchBook Pro
• Smalltalk (computer programming)
• Swift (computer programming)
• Synfig
• TypeScript
• VBScript
• Visual Studio .NET
• cyber security
• data models
• implement ICT safety policies
• implement a virtual private network
• information security strategy
• manage changes in ICT system
• manage online content
• online analytical processing
• use an application-specific interface
• World Wide Web Consortium standards
• augmented reality
• computer programming
• conduct search engine optimisation
• enhance website visibility
• system backup best practice
• use databases
• use spreadsheets software
• web analytics