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Django for Beginners

What is Django?

Django is a high-level Python web framework used to build:

  • Web applications

  • APIs

  • Admin panels

  • Scalable backend systems

Why Django (over Flask)?

Django Flask
Batteries included Micro framework
Built-in admin No admin
ORM included Optional
Slower to start Faster to prototype

👉 Use Django when:

  • You want structure

  • You’re building real products

  • You don’t want to reinvent basics

Prerequisites

  • Python 3.10+

  • pip

  • Virtual environment (recommended)

python --version
pip --version

Virtual Environment (DON’T SKIP THIS)

Most beginners skip this → dependency hell later.

python -m venv venv

Activate:

Windows

venv\Scripts\activate

Mac/Linux

source venv/bin/activate

Install Django

pip install django

Verify:

django-admin --version

Create Django Project

django-admin startproject myproject
cd myproject

Structure:

myproject/
│── manage.py
│── myproject/
│   ├── __init__.py
│   ├── settings.py
│   ├── urls.py
│   ├── asgi.py
│   └── wsgi.py

Key Files (Know this)

  • settings.py → configuration

  • urls.py → URL routing

  • manage.py → command-line utility

▶️ Run Development Server

python manage.py runserver

Visit:

http://127.0.0.1:8000/

If this doesn’t work → don’t proceed.

📦 Create an App (Core Django Concept)

Project = entire system
App = feature/module

python manage.py startapp core

Structure:

core/
├── admin.py
├── apps.py
├── models.py
├── views.py
├── tests.py
└── migrations/

⚙️ Register App

In settings.py:

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',

    'core',  # add this
]

🌐 First View (Hello World)

core/views.py

from django.http import HttpResponse

def home(request):
    return HttpResponse("Hello Django")

🔗 URL Mapping

core/urls.py

from django.urls import path
from .views import home

urlpatterns = [
    path('', home),
]

Connect app URLs

myproject/urls.py

from django.contrib import admin
from django.urls import path, include

urlpatterns = [
    path('admin/', admin.site.urls),
    path('', include('core.urls')),
]

🧠 Django Request Flow (Important)

Browser → urls.py → views.py → response

No magic. Just routing.

🧱 Templates (HTML Rendering)

Create folder:

core/templates/
└── home.html

home.html

<!DOCTYPE html>
<html>
<head>
    <title>Django</title>
</head>
<body>
    <h1>Hello from Template</h1>
</body>
</html>

Update View

from django.shortcuts import render

def home(request):
    return render(request, 'home.html')

📂 Static Files (CSS / JS)

Create:

core/static/core/style.css

style.css

body {
    background: #f4f4f4;
}

Load in template

{% load static %}
<link rel="stylesheet" href="{% static 'core/style.css' %}">

🧮 Models (Database Layer)

core/models.py

from django.db import models

class Student(models.Model):
    name = models.CharField(max_length=100)
    age = models.IntegerField()
    email = models.EmailField(unique=True)

    def __str__(self):
        return self.name

🗄️ Migrations (DB Sync)

python manage.py makemigrations
python manage.py migrate

Never edit DB directly. Django owns it.

🔐 Admin Panel (Superpower)

Create admin user:

python manage.py createsuperuser

Register model:

core/admin.py

from django.contrib import admin
from .models import Student

admin.site.register(Student)

Visit:

http://127.0.0.1:8000/admin

Forms (User Input)

core/forms.py

from django import forms
from .models import Student

class StudentForm(forms.ModelForm):
    class Meta:
        model = Student
        fields = '__all__'

🧠 CRUD View Example

from django.shortcuts import render, redirect
from .forms import StudentForm

def add_student(request):
    form = StudentForm(request.POST or None)
    if form.is_valid():
        form.save()
        return redirect('/')
    return render(request, 'form.html', {'form': form})

❌ Common Beginner Mistakes

❌ Not using virtual env
❌ Forgetting to add app in INSTALLED_APPS
❌ Editing DB manually
❌ Mixing logic in templates
❌ Ignoring migrations

🧩 Django Mental Model (Remember This)

Layer Responsibility
URLs Routing
Views Logic
Templates UI
Models Data
Forms Validation

🔜 What to Learn Next (Order Matters)

  1. Django ORM queries

  2. Authentication system

  3. Django REST Framework (DRF)

  4. Deployment (Gunicorn + Nginx)

  5. PostgreSQL

🧠 Final Advice (No Sugarcoating)

Django rewards discipline.
If you’re lazy with structure → Django will punish you.
If you respect conventions → Django scales beautifully.

If you want:

  • API-only Django

  • Django + React

  • Django REST Framework notes

  • Real-world project README

Say it directly.