FullStack Web Developer 
Demonstration Layer handling the user Interface: Frontend
HTML5
CSS3
JavaScript
JQuery
Plugin Developement
Version Control System: save several version of your project
GIT
Buisiness Logic Layer: Backend Section: Dealing with data authentication: Server Side Langage
PHP
JAVA
.NET
Ruby
Python
DataBase Layer
MySQL
Oracle
MongoDB
Postgres
Deployment Operating System
Ubuntu
Centos
Linux
Web Server
Apache
Nginx
Things to learn
Should be able to work with frontend development
Should be able to work with backend development
Should know at least an Operating System
Should have some knoweldge of Database
Web Servers
Version Control System
Advantages
full stack developer will be in huge demand
The average Salary
70 thousand -120 dollars per year in United States
Docker