There are two popular modules in Drupal that offer eCommerce features. These modules are E-commerce and Ubercart. They include a plethora of features to meet the overall eCommerce requirements of any site.
The Drupal module E-commerce is a contributed module that has been in use since a long. The earlier edition has some limitations that were taken care while building the new version. The latest version of E-commerce module, offers a more flexible and robust architecture. Version 4 permits developers to build on the existent features and come up with additional e-commerce features. The E-commerce module also contains built-in integration with useful sub-modules such as Views, Rules and Chaos tool suite.
Ubercart had been initially designed as an extension of E-commerce module. It was developed to come up with an exhaustive and user-friendly e-commerce solution. Since version 2, the module altered its approach and worked on flexibility and specific API for developers. It has the ability to integrate with many useful modules as well, such as the Content Construction Kit module and Google Analytics module.
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