Whenever a person develops any projects (web/apps) front end and back end from scratch handling UI interface, logics, backend and server side works.
A full stack developer should be familiar with front end technology HTML, CSS and JavaScripts, Angular, React and jQuery etc and for the backend technology should be familiar with programming language Java, Python and PHP etc. And for the backend Oracle, SQL server, MySQL. A full stack developer should be good in Azure or AWS.

He should be aware about basic Devops and good understanding about the version controlling Continuous Integration and Continuous Development (CI/CD).
Develop and Maintain front-end and back-end
A full stack developer is able to work on Web services and interfaces .
Collaboration with department and products owner
Frontend development: HTML, CSS, Java Script, Node and Angular
Backend development: Python, Java, C# and Swift
Data Structure and Algorithms: Arrays, Tree, Graphs
Database management: SQL and MySQL
Version Control: Git, GitHub and GitLab
Operating System: Windows, Linux
Networking: TCP/IP, DNS, HTTP, HTTPS
Cloud Computing: AWS, Azure
Containerization: Docker, Kubernetes
Software Methodology: Agile, Scrum, Kanban
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Practice…. Practice…. Practice……