Full Stack Development involves building both the front end and back end of a website or application. Commonly used programming languages listed by an institute of Full Stack Development Course in Delhi:

1. HTML (HyperText Markup Language): This is used to create the structure of web pages. It tells the browser what to display.

2. CSS (Cascading Style Sheets): CSS is used to style web pages. It controls how HTML elements look, including colors, fonts, and layouts.

3. JavaScript: This language makes web pages interactive. With JavaScript, developers can create dynamic features, like buttons that respond when clicked.

4. Node.js: This is a runtime environment that allows developers to use JavaScript on the server side. It helps in building the back end of applications.

5. Python: Known for its simplicity, Python is often used for back-end development. It has many frameworks, like Django and Flask, that help create web applications.

6. Ruby: Ruby, along with its framework Ruby on Rails, is another popular choice for back-end development.

7. SQL: This language is used for managing databases. It helps in storing and retrieving data for applications.