Introduction

Django is a high-level Python web framework that encourages rapid development and clean, pragmatic design. It's perfect for building complex web applications.

Django's "batteries included" philosophy sets it apart from minimalist frameworks. It ships with an ORM, an admin interface, authentication, form handling, an email backend, and a templating engine , all integrated and working together out of the box. This makes Django an outstanding choice for content-driven applications, SaaS platforms, and data-heavy backends where development speed matters. The framework is trusted by Instagram, Pinterest, Disqus, and Mozilla, demonstrating its ability to scale to significant traffic.

Django Basics

Django follows the MVT (Model-View-Template) architecture pattern. Models define data structure, views handle business logic, and templates manage presentation.

Understanding Django's request/response lifecycle is fundamental to working effectively with the framework. When a request arrives, Django's URL dispatcher matches it to a view function or class. The view performs business logic, typically querying the database through models, and passes data to a template. The template renders HTML which is returned as the HTTP response. This clean separation of concerns makes Django applications predictable and maintainable as they grow.

Organize your code into Django apps , small, reusable modules with focused responsibilities
Keep settings.py configuration in separate files for development, staging, and production
Use Django's built-in User model and authentication system rather than building your own
Follow Django's conventions (naming, file structure) to make your code readable to other Django developers

Models and Migrations

Django's ORM allows you to define database models using Python classes. Migrations handle database schema changes automatically, making version control for your database structure seamless.

Django's ORM supports complex queries including filtering, aggregation, annotation, and prefetching related objects , all through a Pythonic, chainable API. For performance-critical queries, select_related() and prefetch_related() are essential tools for avoiding the N+1 query problem. Use only() and defer() to limit the fields fetched from the database when you don't need the full model instance.

Always run makemigrations and commit migration files alongside model changes
Use select_related() for ForeignKey relationships and prefetch_related() for ManyToMany
Add database indexes to fields frequently used in WHERE clauses or ORDER BY
Write data migrations when you need to transform existing data alongside schema changes

Views and URL Routing

Django's URL dispatcher maps URLs to view functions. Views can be function-based or class-based, providing flexibility in how you structure your application logic.

Class-based views (CBVs) reduce boilerplate for common patterns like list/detail/create/update/delete. Django's generic CBVs (ListView, DetailView, CreateView) provide pagination, form handling, and context injection with minimal code. For REST APIs, Django REST Framework builds on this with ViewSet and ModelSerializer classes that map model fields to API endpoints automatically.

Use function-based views for simple, custom logic; class-based views for standard CRUD patterns
Organize URL patterns in app-level urls.py files and include them in the project urls.py
Use named URL patterns and the reverse() function to avoid hardcoding URLs
Apply decorators (@login_required, @permission_required) to protect views declaratively

Templates and Static Files

Django's template system allows you to create dynamic HTML pages. Templates support template inheritance, filters, and tags for building reusable UI components.

Template inheritance is one of Django's most powerful features for maintaining consistent layouts. A base template defines the page shell with named blocks, and child templates override only the blocks they need to change. Custom template tags and filters allow you to encapsulate reusable presentation logic that doesn't belong in views. For modern frontends, Django serves equally well as a pure API backend with a React or Vue.js frontend consuming the Django REST Framework API.

Define a base.html template with common structure and {% block %} hooks
Use {% include %} for reusable partials and {% extends %} for page inheritance
Serve static files via a CDN in production using django-storages with S3 or similar
Use {% load static %} and {% static 'path' %} to reference static asset URLs correctly

Django Admin Interface

Django provides a built-in admin interface that automatically generates a user-friendly interface for managing your application's data, perfect for content management.

The Django admin is a powerful internal tool that becomes even more valuable when customized. You can add list filters, search fields, inline editing for related models, and custom actions (bulk operations). For teams building content-heavy products, the admin can serve as a fully functional CMS with relatively minimal configuration. Third-party packages like django-unfold and django-jazzmin provide modern UI skins that dramatically improve the admin's visual experience.

Register models with custom ModelAdmin classes to control list columns, filters, and search fields
Use InlineModelAdmin to edit related objects on the same page as the parent model
Add custom actions for bulk operations that can be run from the changelist view
Restrict admin access with has_view_permission, has_change_permission, and related methods