PocketFlow-Tutorial-Codebase-Knowledge/docs/Flask/index.md

---
layout: default
title: "Flask"
nav_order: 11
has_children: true
---

# Tutorial: Flask

Flask is a lightweight **web framework** for Python.
It helps you build web applications by handling incoming *web requests* and sending back *responses*.
Flask provides tools for **routing** URLs to your Python functions, managing *request data*, creating *responses*, and using *templates* to generate HTML.


**Source Repository:** [https://github.com/pallets/flask/tree/ab8149664182b662453a563161aa89013c806dc9/src/flask](https://github.com/pallets/flask/tree/ab8149664182b662453a563161aa89013c806dc9/src/flask)

```mermaid
flowchart TD
    A0["0: Application Object (Flask)"]
    A1["1: Blueprints"]
    A2["2: Routing System"]
    A3["3: Request and Response Objects"]
    A4["4: Application and Request Contexts"]
    A5["5: Context Globals (current_app, request, session, g)"]
    A6["6: Configuration (Config)"]
    A7["7: Templating (Jinja2 Integration)"]
    A0 -- "Registers" --> A1
    A0 -- "Uses" --> A2
    A0 -- "Handles" --> A3
    A0 -- "Manages" --> A4
    A0 -- "Holds" --> A6
    A0 -- "Integrates" --> A7
    A1 -- "Defines routes using" --> A2
    A2 -- "Matches URL from" --> A3
    A3 -- "Bound within" --> A4
    A4 -- "Enables access to" --> A5
    A7 -- "Accesses" --> A5
```