Thanks for clarifying this topic. It helps me better understand context now!
ram_vishy
sic
Contexts are to Controllers how Presenters are to Views.
Presenters encompass all the stuff that the view will consume.
Contexts encompass all the stuff that the controller will consume.
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kif
AstonJ
In the book-programming-phoenix they say (about Contexts):
All good application programmers must learn how to break down complex ideas into discrete steps. The opposite is also true. To build a beautiful API, you must be able to coalesce discrete functions into ideas by strategically layering and grouping functions.
Every library we use, and even Elixir itself, is structured based on those ideas. For example, any time you call Logger.debug from Elixir’s standard library, you are accessing the Logger context. Internally, Logger may be broken into multiple modules, but for us, everything is exposed through a simple, well-defined public API of the Logger module.
Phoenix projects are structured like Elixir libraries and projects.
If you haven’t got the book I highly recommend it! I’m hoping we can start a book club for it soon, if anyone’s interested in joining, please let me know 
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