Developer's Guide

Module file tree
All PrestaShop modules are found in the /modules folder, which is at the
root of the PrestaShop main folder. This is true for both default modules
(provided with PrestaShop) and 3rd-party modules that are subsequently
installed.
Each module has its own sub-folder inside the /modules folder: /bankwire,
/birthdaypresent, etc.
Basic structure of a module
All modules use the same basic structure, which makes it easier to learn
by observing existing modules' source code.
Let's create a simple first module; this will enable us to better describe its
structure. We'll call it "My module".
Let's first create the module folder. It should have the same name as the
module, with no space, only alphanumerical characters, the hyphen and
the underscore, all in lowercase: /mymodule.
This folder must contain a PHP file of the same name, which will handle
most of the processing: mymodule.php.
That is enough for a very basic module, but obviously more files and
folders can complement it.
The front-office part of the module is defined in a .tpl file placed at the
root of the module's folder. TPL files can have just about any name. It