Django is a free and open source web application framework, written in Python. A web framework is a set of components that helps you to develop websites faster and easier.
When you're building a website, you always need a similar set of components: a way to handle user authentication (signing up, signing in, signing out), a management panel for your website, forms, a way to upload files, etc.
Django's primary goal is to ease the creation of complex, database-driven websites. Django emphasizes reusability and "pluggability" of components, rapid development, and the principle of don't repeat yourself. Python is used throughout, even for settings, files, and data models. Django also provides an optional administrative create, read, update and delete interface that is generated dynamically through introspection and configured via admin models.
Django is a prominent member of a new generation of Web frameworks.Luckily for you other people long ago noticed that web developers face similar problems when building a new site, so they teamed up and created frameworks (Django is one of them) that give you ready-made components you can use.