Web developers typically either develop in proprietary technologies such as Microsoft or they subscribe to the open source model of software and software development.
The open source model has been growing in strength and numbers over several years and the benefits of this model are now being considered by businesses and government departments alike. As such, previous involvement in open source projects can be a real plus for serious web developers. Without a doubt, the ability to use, configure and develop upon open source platforms is a key skills set in website and web application development.
Some baseline Web Development skills/technologies
XHTML / HTML
Server side scripting (e.g. php, asp, JSP)
Database skills (SQL, MySQL, Oracle etc)