# Week 1

In this session we will focus on Express.js as a framework for building HTTP APIs. Instead of writing everything from scratch in Node, we will use Express to structure routes, plug in middleware, and handle requests and responses in a predictable way – including using clear status codes and basic error handling.

## Contents

* [Preparation](/course-content/backend/node/week1/preparation.md)
* [Session Plan](/course-content/backend/node/week1/session-plan.md) (for mentors)
* [Assignment](/course-content/backend/node/week1/assignment.md)

## Session Learning Goals

By the end of this session, you will be able to:

* [ ] Explain what Express is and describe why it is used for building backend applications.
* [ ] Implement routing in Express to handle `GET` HTTP requests, endpoints and parameters.
* [ ] Use logging and debugging tools to monitor and troubleshoot Node.js applications.
* [ ] Apply middleware functions in Express to process and transform requests and responses.
* [ ] Design and implement basic error handling for HTTP APIs using appropriate status codes.
* [ ] Use Postman to send requests to your Express API and inspect responses.


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