Web fundamentals such as HTML, JavaScript, and CSS
CSS preprocessors such as Sass or LESS
JavaScript frameworks such as AngularJS, React, or Ember etc., or JS-based build tools like Grunt, Gulp, and Bower
Libraries like jQuery or
Front-end (CSS) frameworks such as Foundation or Bootstrap
AJAX
Back-End
API design and development
CRUD (Create, Read, Update, Delete)
RESTful Services
Web fundamentals such as HTML, JavaScript, and CSS
Server-side languages such as PHP, Java, JavaScript, and .Net
Database technologies such as MySQL, Oracle, PostgreSQL, and MongoDB.
Web server technologies such as , J2EE, Apache, Nginx, ISS, etc.
Frameworks related to their server-side language of choice such as , Ruby on Rails, CakePHP, etc.